Prevents future UT build issues addresses opensearch-project#2967

Depending on the GitHub CI workflow executes it will invoke ./gradlew build which will run tests on random parameters everytime, there are local-code's that will break a build one of them being az-Cyrl. The solution here was preventing (explicitly writing the local to be set to en-US) Github actions building on these random parameters that will interupt a build and lose time. Manual testing was done to prove that using this flag breaks a build, you can check the issue opensearch-project#2967 or you can run ./gradlew build -Dtests.local=az-Cyrl to see it breaks

Signed-off-by: Brian Flores <iflorbri@amazon.com>

.github/workflows/CI-workflow.yml

@@ -65,7 +65,7 @@ jobs:
                                export COHERE_KEY=`aws secretsmanager get-secret-value --secret-id github_cohere_key --query SecretString --output text` &&
                                echo "::add-mask::$OPENAI_KEY" &&
                                echo "::add-mask::$COHERE_KEY" &&
-                               echo "build and run tests" && ./gradlew build &&
+                               echo "build and run tests" && ./gradlew build -Dtests.locale=en-US &&
                                echo "Publish to Maven Local" && ./gradlew publishToMavenLocal &&
                                echo "Multi Nodes Integration Testing" && ./gradlew integTest -PnumNodes=3'
           plugin=`basename $(ls plugin/build/distributions/*.zip)`