[Backport 2.0] [Remove] Type from nested fields using new metadata field mapper

[nknize]

Backport 6b641d2 from #3004

[nknize]

Note: let's not merge until 2.0 RC is built.

[dreamer-89]

This is failing on spotless java check task due to one unused import.

Execution failed for task ':server:spotlessJavaCheck'.
> The following files had format violations:
      src/test/java/org/opensearch/indices/IndicesModuleTests.java
          @@ -41,7 +41,6 @@
           import·org.opensearch.index.mapper.Mapper;
           import·org.opensearch.index.mapper.MapperParsingException;
           import·org.opensearch.index.mapper.MetadataFieldMapper;
          -import·org.opensearch.index.mapper.NestedPathFieldMapper;
           import·org.opensearch.index.mapper.RoutingFieldMapper;
           import·org.opensearch.index.mapper.SeqNoFieldMapper;
           import·org.opensearch.index.mapper.SourceFieldMapper;
  Run './gradlew :server:spotlessApply' to fix these violations.

[opensearch-ci-bot]

❌   Gradle Check failure 8794cce
Log 4838

Reports 4838

[opensearch-ci-bot]

❌   Gradle Check failure 578a26d
Log 4839

Reports 4839

[dreamer-89]

Lastest job run failed on task :buildSrc:pluginUnderTestMetadata. Doesn't look related to code change, probably transient one. Refiring.

> Task :distribution:bwc:minor:buildBwcLinuxTar
 [1.4.0] 
 [1.4.0] > Task :buildSrc:compileGroovy
 [1.4.0] Note: /var/CITOOL/workflow/OpenSearch_CI/PR_Checks/Gradle_Check/search/distribution/bwc/minor/build/bwc/checkout-1.x/buildSrc/src/main/groovy/org/opensearch/gradle/test/TestWithSslPlugin.java uses unchecked or unsafe operations.
 [1.4.0] Note: Recompile with -Xlint:unchecked for details.
 [1.4.0] WARNING: An illegal reflective access operation has occurred
 [1.4.0] WARNING: Illegal reflective access by org.codehaus.groovy.reflection.CachedClass (file:/home/ubuntu/.gradle/wrapper/dists/gradle-6.6.1-all/ejrtlte9hlw8v6ii20a9584rs/gradle-6.6.1/lib/groovy-all-1.3-2.5.12.jar) to method java.util.AbstractCollection.hugeCapacity(int)
 [1.4.0] WARNING: Please consider reporting this to the maintainers of org.codehaus.groovy.reflection.CachedClass
 [1.4.0] WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
 [1.4.0] WARNING: All illegal access operations will be denied in a future release
 [1.4.0] 
 [1.4.0] > Task :buildSrc:generateVersionProperties
 [1.4.0] > Task :buildSrc:pluginDescriptors
 [1.4.0] > Task :buildSrc:processResources
 [1.4.0] > Task :buildSrc:classes
 [1.4.0] > Task :buildSrc:jar
 [1.4.0] > Task :buildSrc:assemble
 [1.4.0] > Task :buildSrc:pluginUnderTestMetadata FAILED
 [1.4.0] 
 [1.4.0] FAILURE: Build failed with an exception.
 [1.4.0] 
 [1.4.0] * What went wrong:
 [1.4.0] Execution failed for task ':buildSrc:pluginUnderTestMetadata'.
 [1.4.0] > Could not resolve all files for configuration ':buildSrc:runtimeClasspath'.
 [1.4.0]    > Could not find nebula-core-3.0.0.jar (com.netflix.nebula:nebula-core:3.0.0).
 [1.4.0]      Searched in the following locations:
 [1.4.0]          https://plugins.gradle.org/m2/com/netflix/nebula/nebula-core/3.0.0/nebula-core-3.0.0.jar
 [1.4.0] 
 [1.4.0] * Try:
 [1.4.0] Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
 [1.4.0] 
 [1.4.0] * Get more help at https://help.gradle.org
 [1.4.0] 
 [1.4.0] BUILD FAILED in 1m 34s

[dreamer-89]

start gradle check

[opensearch-ci-bot]

❌   Gradle Check failure 578a26d
Log 4840

Reports 4840

[nknize]

Related to merge conflict:

REPRODUCE WITH: ./gradlew ':server:test' --tests "org.opensearch.indices.IndicesModuleTests.testBuiltinMappers" -Dtests.seed=9AE7B29E887AF323 -Dtests.security.manager=true -Dtests.jvm.argline="-XX:TieredStopAtLevel=1 -XX:ReservedCodeCacheSize=64m" -Dtests.locale=es-BO -Dtests.timezone=Asia/Hong_Kong -Druntime.java=17

org.opensearch.indices.IndicesModuleTests > testBuiltinMappers FAILED
    java.lang.AssertionError: expected:<10> but was:<11>
        at __randomizedtesting.SeedInfo.seed([9AE7B29E887AF323:287AF3F9128E5A44]:0)
        at org.junit.Assert.fail(Assert.java:89)
        at org.junit.Assert.failNotEquals(Assert.java:835)
        at org.junit.Assert.assertEquals(Assert.java:647)
        at org.junit.Assert.assertEquals(Assert.java:633)
        at org.opensearch.indices.IndicesModuleTests.testBuiltinMappers(IndicesModuleTests.java:111)

I'll fix shortly.

[opensearch-ci-bot]

✅   Gradle Check success 6b39739
Log 4841

Reports 4841