Add Opensearch version 2 to unit tests and update Elasticsearch versions

What does this MR do and why?

Changes Opensearch unit tests in CI from version 1.2.4 to the latest version 2.0.0

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.gitlab/ci/rails/shared.gitlab-ci.yml

@@ -128,6 +128,12 @@ include:
     - .use-pg12-opensearch1-ee
     - .rails:rules:run-search-tests
 
+.rspec-ee-base-pg12-opensearch2:
+  extends:
+    - .rspec-base
+    - .use-pg12-opensearch2-ee
+    - .rails:rules:run-search-tests
+
 .rspec-ee-base-pg13:
   extends:
     - .rspec-base