[ML] Adjust versions and unmute BWC tests after backport of #59254

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ml/dataframe/DataFrameAnalyticsConfig.java

@@ -173,11 +173,7 @@ public DataFrameAnalyticsConfig(StreamInput in) throws IOException {
         } else {
             allowLazyStart = false;
         }
-        if (in.getVersion().onOrAfter(Version.V_8_0_0)) {
-            maxNumThreads = in.readVInt();
-        } else {
-            maxNumThreads = 1;
-        }
+        maxNumThreads = in.readVInt();
     }
 
     public String getId() {
@@ -289,9 +285,7 @@ public void writeTo(StreamOutput out) throws IOException {
         if (out.getVersion().onOrAfter(Version.V_7_5_0)) {
             out.writeBoolean(allowLazyStart);
         }
-        if (out.getVersion().onOrAfter(Version.V_8_0_0)) {
-            out.writeVInt(maxNumThreads);
-        }
+        out.writeVInt(maxNumThreads);
     }
 
     @Override

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ml/dataframe/DataFrameAnalyticsConfigUpdate.java

@@ -5,7 +5,6 @@
  */
 package org.elasticsearch.xpack.core.ml.dataframe;
 
-import org.elasticsearch.Version;
 import org.elasticsearch.common.Nullable;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
@@ -66,11 +65,7 @@ public DataFrameAnalyticsConfigUpdate(StreamInput in) throws IOException {
         this.description = in.readOptionalString();
         this.modelMemoryLimit = in.readOptionalWriteable(ByteSizeValue::new);
         this.allowLazyStart = in.readOptionalBoolean();
-        if (in.getVersion().onOrAfter(Version.V_8_0_0)) {
-            this.maxNumThreads = in.readOptionalVInt();
-        } else {
-            this.maxNumThreads = null;
-        }
+        this.maxNumThreads = in.readOptionalVInt();
     }
 
     @Override
@@ -79,9 +74,7 @@ public void writeTo(StreamOutput out) throws IOException {
         out.writeOptionalString(description);
         out.writeOptionalWriteable(modelMemoryLimit);
         out.writeOptionalBoolean(allowLazyStart);
-        if (out.getVersion().onOrAfter(Version.V_8_0_0)) {
-            out.writeOptionalVInt(maxNumThreads);
-        }
+        out.writeOptionalVInt(maxNumThreads);
     }
 
     public String getId() {

x-pack/plugin/core/src/test/java/org/elasticsearch/xpack/core/ml/dataframe/DataFrameAnalyticsConfigTests.java

@@ -124,9 +124,6 @@ protected DataFrameAnalyticsConfig mutateInstanceForVersion(DataFrameAnalyticsCo
             builder.setCreateTime(null);
             builder.setVersion(null);
         }
-        if (version.before(Version.V_8_0_0)) {
-            builder.setMaxNumThreads(null);
-        }
         return builder.build();
     }
 

x-pack/qa/rolling-upgrade/src/test/resources/rest-api-spec/test/mixed_cluster/90_ml_data_frame_analytics_crud.yml

@@ -1,8 +1,3 @@
-setup:
-  - skip:
-      version: "all"
-      reason:  "Until backport of https://github.com/elastic/elasticsearch/pull/59254"
-
 ---
 "Get old outlier_detection job":
 

x-pack/qa/rolling-upgrade/src/test/resources/rest-api-spec/test/old_cluster/90_ml_data_frame_analytics_crud.yml

@@ -1,7 +1,4 @@
 setup:
-  - skip:
-      version: "all"
-      reason:  "Until backport of https://github.com/elastic/elasticsearch/pull/59254"
 
   - do:
       index:

x-pack/qa/rolling-upgrade/src/test/resources/rest-api-spec/test/upgraded_cluster/90_ml_data_frame_analytics_crud.yml

@@ -1,8 +1,3 @@
-setup:
-  - skip:
-      version: "all"
-      reason:  "Until backport of https://github.com/elastic/elasticsearch/pull/59254"
-
 ---
 "Get old cluster outlier_detection job":