Lower minimum compatibility of aggregate_metric_double field (#65000)

After merging aggregate_metric_double field type to 7.11.0 (#64939),
this PR lowers the minimum compatibility veersion from 8.0.0 to 7.11.0

Relates to #56745

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/aggregatemetric/AggregateMetricFeatureSetUsage.java

@@ -25,7 +25,7 @@ public class AggregateMetricFeatureSetUsage extends XPackFeatureSet.Usage {
     }
 
     @Override public Version getMinimalSupportedVersion() {
-        return Version.V_8_0_0;
+        return Version.V_7_11_0;
     }
 
     @Override

x-pack/plugin/src/test/resources/rest-api-spec/test/aggregate-metrics/10_basic.yml

@@ -1,8 +1,8 @@
 ---
 "Test exists query on aggregate metric field":
   - skip:
-      version: " - 7.99.99"
-      reason: "Aggregate metric fields are currently only implemented in 8.0."
+      version: " - 7.10.99"
+      reason: "Aggregate metric fields have been added in 7.11"
 
   - do:
       indices.create:
@@ -58,8 +58,8 @@
 ---
 "Test term query on aggregate metric field":
   - skip:
-      version: " - 7.99.99"
-      reason: "Aggregate metric fields are currently only implemented in 8.0."
+      version: " - 7.10.99"
+      reason: "Aggregate metric fields have been added in 7.11"
 
   - do:
       indices.create:
@@ -134,8 +134,8 @@
 ---
 "Test range query on aggregate metric field":
   - skip:
-      version: " - 7.99.99"
-      reason: "Aggregate metric fields are currently only implemented in 8.0."
+      version: " - 7.10.99"
+      reason: "Aggregate metric fields have been added in 7.11"
 
   - do:
       indices.create:
@@ -211,8 +211,8 @@
 ---
 "Sort":
   - skip:
-      version: " - 7.99.99"
-      reason: "Aggregate metric fields are currently only implemented in 8.0."
+      version: " - 7.10.99"
+      reason: "Aggregate metric fields have been added in 7.11"
 
   - do:
       indices.create:

x-pack/plugin/src/test/resources/rest-api-spec/test/aggregate-metrics/20_min_max_agg.yml

@@ -32,8 +32,8 @@ setup:
 ---
 "Test min_max aggs":
   - skip:
-      version: " - 7.99.99"
-      reason: "Aggregate metric fields are currently only implemented in 8.0."
+      version: " - 7.10.99"
+      reason: "Aggregate metric fields have been added in 7.11"
 
   - do:
       search:
@@ -56,8 +56,8 @@ setup:
 ---
 "Test min_max aggs with query":
   - skip:
-      version: " - 7.99.99"
-      reason: "Aggregate metric fields are currently only implemented in 8.0."
+      version: " - 7.10.99"
+      reason: "Aggregate metric fields have been added in 7.11"
 
   - do:
       search:

x-pack/plugin/src/test/resources/rest-api-spec/test/aggregate-metrics/30_sum_agg.yml

@@ -28,8 +28,8 @@ setup:
 ---
 "Test sum agg":
   - skip:
-      version: " - 7.99.99"
-      reason: "Aggregate metric fields are currently only implemented in 8.0."
+      version: " - 7.10.99"
+      reason: "Aggregate metric fields have been added in 7.11"
 
   - do:
       search:
@@ -47,8 +47,8 @@ setup:
 ---
 "Test sum agg with query":
   - skip:
-      version: " - 7.99.99"
-      reason: "Aggregate metric fields are currently only implemented in 8.0."
+      version: " - 7.10.99"
+      reason: "Aggregate metric fields have been added in 7.11"
 
   - do:
       search:

x-pack/plugin/src/test/resources/rest-api-spec/test/aggregate-metrics/40_avg_agg.yml

@@ -28,8 +28,8 @@ setup:
 ---
 "Test avg agg":
   - skip:
-      version: " - 7.99.99"
-      reason: "Aggregate metric fields are currently only implemented in 8.0."
+      version: " - 7.10.99"
+      reason: "Aggregate metric fields have been added in 7.11"
 
   - do:
       search:
@@ -47,8 +47,8 @@ setup:
 ---
 "Test avg agg with query":
   - skip:
-      version: " - 7.99.99"
-      reason: "Aggregate metric fields are currently only implemented in 8.0."
+      version: " - 7.10.99"
+      reason: "Aggregate metric fields have been added in 7.11"
 
   - do:
       search:

x-pack/plugin/src/test/resources/rest-api-spec/test/aggregate-metrics/50_value_count_agg.yml

@@ -28,8 +28,8 @@ setup:
 ---
 "Test value_count agg":
   - skip:
-      version: " - 7.99.99"
-      reason: "Aggregate metric fields are currently only implemented in 8.0."
+      version: " - 7.10.99"
+      reason: "Aggregate metric fields have been added in 7.11"
 
   - do:
       search:
@@ -47,8 +47,8 @@ setup:
 ---
 "Test value_count agg with query":
   - skip:
-      version: " - 7.99.99"
-      reason: "Aggregate metric fields are currently only implemented in 8.0."
+      version: " - 7.10.99"
+      reason: "Aggregate metric fields have been added in 7.11"
 
   - do:
       search:

x-pack/plugin/src/test/resources/rest-api-spec/test/aggregate-metrics/80_raw_agg_metric_aggs.yml

@@ -59,8 +59,8 @@ setup:
 ---
 "Test mixed aggregations":
   - skip:
-      version: " - 7.99.99"
-      reason: "Aggregate metric fields are currently only implemented in 8.0."
+      version: " - 7.10.99"
+      reason: "Aggregate metric fields have been added in 7.11"
 
   - do:
       search:
@@ -94,8 +94,8 @@ setup:
 ---
 "Test mixed aggregations with query":
   - skip:
-      version: " - 7.99.99"
-      reason: "Aggregate metric fields are currently only implemented in 8.0."
+      version: " - 7.10.99"
+      reason: "Aggregate metric fields have been added in 7.11"
 
   - do:
       search: