Fix test fixture dependencies in eclipse (#63979)

- Fix test fixture dependencies in eclipse
- explain issue inline

build.gradle

@@ -31,6 +31,7 @@ import org.gradle.plugins.ide.eclipse.model.SourceFolder
 import org.gradle.util.DistributionLocator
 import org.gradle.util.GradleVersion
 import static org.elasticsearch.gradle.util.GradleUtils.maybeConfigure
+import org.gradle.plugins.ide.eclipse.model.ProjectDependency
 
 plugins {
   id 'lifecycle-base'
@@ -330,6 +331,17 @@ allprojects {
         i++;
         folder.output = "build-eclipse/" + i
       }
+
+      // Starting with Gradle 6.7 test dependencies are not exposed by eclipse
+      // projects by default. This breaks project dependencies using the `java-test-fixtures` plugin
+      // or dependencies on other projects manually declared testArtifacts configurations
+      // This issue is tracked in gradle issue tracker.
+      // See https://github.com/gradle/gradle/issues/14932 for further details
+      classpath.entries.findAll {
+        it instanceof ProjectDependency
+      }.each {
+        it.entryAttributes.remove('without_test_code')
+      }
     }
   }
   /*