Remove esql version from docs (#108933)

Follow-up to https://github.com/elastic/elasticsearch/pull/108919. The
latter needs to be merged first to have the docs tests pass, as it makes
the version parameter optional in requests.

docs/reference/esql/esql-async-query-api.asciidoc

@@ -24,8 +24,7 @@ POST /_query/async
     | SORT year
     | LIMIT 5
   """,
-  "wait_for_completion_timeout": "2s",
-  "version": "2024.04.01"
+  "wait_for_completion_timeout": "2s"
 }
 ----
 // TEST[setup:library]

docs/reference/esql/esql-query-api.asciidoc

@@ -16,8 +16,7 @@ POST /_query
     | STATS MAX(page_count) BY year
     | SORT year
     | LIMIT 5
-  """,
-  "version": "2024.04.01"
+  """
 }
 ----
 // TEST[setup:library]
@@ -79,10 +78,6 @@ For syntax, refer to <<esql-locale-param>>.
 `query`::
 (Required, string) {esql} query to run. For syntax, refer to <<esql-syntax>>.
 
-`version`::
-(Required, string) {esql} language version. Can be sent in short or long form, e.g.
-`2024.04.01` or `2024.04.01.🚀`. See <<esql-version>> for details.
-
 [discrete]
 [role="child_attributes"]
 [[esql-query-api-response-body]]

docs/reference/esql/esql-rest.asciidoc

@@ -16,8 +16,7 @@ The <<esql-query-api,{esql} query API>> accepts an {esql} query string in the
 ----
 POST /_query?format=txt
 {
-  "query": "FROM library | KEEP author, name, page_count, release_date | SORT page_count DESC | LIMIT 5",
-  "version": "2024.04.01"
+  "query": "FROM library | KEEP author, name, page_count, release_date | SORT page_count DESC | LIMIT 5"
 }
 ----
 // TEST[setup:library]
@@ -56,8 +55,7 @@ POST /_query?format=txt
     | KEEP author, name, page_count, release_date
     | SORT page_count DESC
     | LIMIT 5
-  """,
-  "version": "2024.04.01"
+  """
 }
 ----
 // TEST[setup:library]
@@ -145,8 +143,7 @@ POST /_query?format=txt
         "lte": 200
       }
     }
-  },
-  "version": "2024.04.01"
+  }
 }
 ----
 // TEST[setup:library]
@@ -182,8 +179,7 @@ POST /_query?format=json
     | SORT page_count DESC
     | LIMIT 5
   """,
-  "columnar": true,
-  "version": "2024.04.01"
+  "columnar": true
 }
 ----
 // TEST[setup:library]
@@ -230,8 +226,7 @@ POST /_query
           | EVAL birth_date = date_parse(birth_date_string)
           | EVAL month_of_birth = DATE_FORMAT("MMMM",birth_date)
           | LIMIT 5
-   """,
-  "version": "2024.04.01"
+   """
 }
 ----
 // TEST[setup:library]
@@ -254,8 +249,7 @@ POST /_query
     | STATS count = COUNT(*) by year
     | WHERE count > 0
     | LIMIT 5
-  """,
-  "version": "2024.04.01"
+  """
 }
 ----
 // TEST[setup:library]
@@ -276,8 +270,7 @@ POST /_query
     | WHERE count > ?
     | LIMIT 5
   """,
-  "params": [300, "Frank Herbert", 0],
-  "version": "2024.04.01"
+  "params": [300, "Frank Herbert", 0]
 }
 ----
 // TEST[setup:library]
@@ -311,8 +304,7 @@ POST /_query/async
     | SORT year
     | LIMIT 5
   """,
-  "wait_for_completion_timeout": "2s",
-  "version": "2024.04.01"
+  "wait_for_completion_timeout": "2s"
 }
 ----
 // TEST[setup:library]

docs/reference/esql/esql-using.asciidoc

@@ -18,12 +18,8 @@ Using {esql} to query across multiple clusters.
 <<esql-task-management>>::
 Using the <<tasks,task management API>> to list and cancel {esql} queries.
 
-<<esql-version>>::
-Information about {esql} language versions.
-
 include::esql-rest.asciidoc[]
 include::esql-kibana.asciidoc[]
 include::esql-security-solution.asciidoc[]
 include::esql-across-clusters.asciidoc[]
 include::task-management.asciidoc[]
-include::esql-version.asciidoc[]

docs/reference/esql/esql-version.asciidoc

@@ -1,49 +0,0 @@
-[[esql-version]]
-=== {esql} language versions
-
-++++
-<titleabbrev>Language versions</titleabbrev>
-++++
-
-[discrete]
-[[esql-versions-released]]
-==== Released versions
-
-* Version `2024.04.01`
-
-[discrete]
-[[esql-versions-explanation]]
-==== How versions work
-
-{esql} language versions are independent of {es} versions.
-Versioning the language ensures that your queries will always
-remain valid, independent of new {es} and {esql} releases. And it lets us
-evolve ESQL as we learn more from people using it. We don't plan to make
-huge changes to it, but we know we've made mistakes and we don't want those
-to live forever.
-
-For instance, the following query will remain valid, even if a future
-version of {esql} introduces syntax changes or changes how the used
-commands or functions work.
-
-[source,console]
-----
-POST /_query?format=txt
-{
-  "version": "2024.04.01",
-  "query": """
-    FROM library
-    | EVAL release_month = DATE_TRUNC(1 month, release_date)
-    | KEEP release_month
-    | SORT release_month ASC
-    | LIMIT 3
-  """
-}
-----
-// TEST[setup:library]
-
-We won't make breaking changes to released {esql} versions and
-versions will remain supported until they are deprecated.
-New features, bug fixes, and performance improvements
-will continue to be added to released {esql} versions,
-provided they do not involve breaking changes.

docs/reference/esql/multivalued-fields.asciidoc

@@ -17,8 +17,7 @@ POST /mv/_bulk?refresh
 
 POST /_query
 {
-  "query": "FROM mv | LIMIT 2",
-  "version": "2024.04.01"
+  "query": "FROM mv | LIMIT 2"
 }
 ----
 
@@ -66,8 +65,7 @@ POST /mv/_bulk?refresh
 
 POST /_query
 {
-  "query": "FROM mv | LIMIT 2",
-  "version": "2024.04.01"
+  "query": "FROM mv | LIMIT 2"
 }
 ----
 
@@ -108,8 +106,7 @@ POST /mv/_bulk?refresh
 
 POST /_query
 {
-  "query": "FROM mv | LIMIT 2",
-  "version": "2024.04.01"
+  "query": "FROM mv | LIMIT 2"
 }
 ----
 
@@ -151,8 +148,7 @@ POST /mv/_bulk?refresh
 
 POST /_query
 {
-  "query": "FROM mv | EVAL b=TO_STRING(b) | LIMIT 2",
-  "version": "2024.04.01"
+  "query": "FROM mv | EVAL b=TO_STRING(b) | LIMIT 2"
 }
 ----
 
@@ -175,7 +171,7 @@ POST /_query
 ==== Functions
 
 Unless otherwise documented functions will return `null` when applied to a multivalued
-field. This behavior may change in a later version.
+field.
 
 [source,console,id=esql-multivalued-fields-mv-into-null]
 ----
@@ -190,8 +186,7 @@ POST /mv/_bulk?refresh
 ----
 POST /_query
 {
-  "query": "FROM mv | EVAL b + 2, a + b | LIMIT 4",
-  "version": "2024.04.01"
+  "query": "FROM mv | EVAL b + 2, a + b | LIMIT 4"
 }
 ----
 // TEST[continued]
@@ -230,8 +225,7 @@ Work around this limitation by converting the field to single value with one of:
 ----
 POST /_query
 {
-  "query": "FROM mv | EVAL b=MV_MIN(b) | EVAL b + 2, a + b | LIMIT 4",
-  "version": "2024.04.01"
+  "query": "FROM mv | EVAL b=MV_MIN(b) | EVAL b + 2, a + b | LIMIT 4"
 }
 ----
 // TEST[continued]