Suppress searchable snapshots docs in releases (#58556)

This commit adds conditional logic to the docs to avoid including any
docs on searchable snapshots in released versions.

docs/reference/ilm/actions/ilm-delete.asciidoc

@@ -6,6 +6,7 @@ Phases allowed: delete.
 
 Permanently removes the index.
 
+ifdef::permanently-unreleased-branch[]
 [[ilm-delete-options]]
 ==== Options
 
@@ -15,6 +16,7 @@ Deletes the searchable snapshot created in the cold phase.
 Defaults to `true`.
 This option is applicable when the <<ilm-searchable-snapshot-action,searchable
 snapshot>> action is used in the cold phase.
+endif::[]
 
 [[ilm-delete-action-ex]]
 ==== Example

docs/reference/ilm/ilm-actions.asciidoc

@@ -25,9 +25,11 @@ Block write operations to the index.
 Remove the index as the write index for the rollover alias and 
 start indexing to a new index.
 
+ifdef::permanently-unreleased-branch[]
 [[ilm-searchable-snapshot-action]]<<ilm-searchable-snapshot, Searchable snapshot>>::
 Take a snapshot of the managed index in the configured repository
 and mount it as a searchable snapshot.
+endif::[]
 
 [[ilm-set-priority-action]]<<ilm-set-priority,Set priority>>::
 Lower the priority of an index as it moves through the lifecycle
@@ -38,7 +40,12 @@ Reduce the number of primary shards by shrinking the index into a new index.
 
 [[ilm-unfollow-action]]<<ilm-unfollow,Unfollow>>::
 Convert a follower index to a regular index.
+ifdef::permanently-unreleased-branch[]
+Performed automatically before a rollover or shrink action.
+endif::[]
+ifndef::permanently-unreleased-branch[]
 Performed automatically before a rollover, shrink, or searchable snapshot action. 
+endif::[]
 
 [[ilm-wait-for-snapshot-action]]<<ilm-wait-for-snapshot,Wait for snapshot>>::
 Ensure that a snapshot exists before deleting the index. 
@@ -49,7 +56,9 @@ include::actions/ilm-forcemerge.asciidoc[]
 include::actions/ilm-freeze.asciidoc[]
 include::actions/ilm-readonly.asciidoc[]
 include::actions/ilm-rollover.asciidoc[]
+ifdef::permanently-unreleased-branch[]
 include::actions/ilm-searchable-snapshot.asciidoc[]
+endif::[]
 include::actions/ilm-set-priority.asciidoc[]
 include::actions/ilm-shrink.asciidoc[]
 include::actions/ilm-unfollow.asciidoc[]

docs/reference/rest-api/index.asciidoc

@@ -32,7 +32,9 @@ endif::[]
 * <<indices-reload-analyzers,Reload Search Analyzers API>>
 * <<rollup-apis,Rollup APIs>>
 * <<search, Search APIs>>
+ifdef::permanently-unreleased-branch[]
 * <<searchable-snapshots-apis, Searchable snapshots APIs>>
+endif::[]
 * <<security-api,Security APIs>>
 * <<snapshot-restore-apis,Snapshot and restore APIs>>
 * <<snapshot-lifecycle-management-api,Snapshot lifecycle management APIs>>
@@ -65,7 +67,9 @@ include::{es-repo-dir}/rollup/rollup-api.asciidoc[]
 include::{es-repo-dir}/search.asciidoc[]
 include::{es-repo-dir}/searchable-snapshots/apis/searchable-snapshots-apis.asciidoc[]
 include::{xes-repo-dir}/rest-api/security.asciidoc[]
+ifdef::permanently-unreleased-branch[]
 include::{es-repo-dir}/snapshot-restore/apis/snapshot-restore-apis.asciidoc[]
+endif::[]
 include::{es-repo-dir}/slm/apis/slm-api.asciidoc[]
 include::{es-repo-dir}/transform/apis/index.asciidoc[]
 include::usage.asciidoc[]