Update default lang tag for PR builds

.github/workflows/build-with-bal-test-graalvm.yml

@@ -42,7 +42,7 @@ jobs:
         if: ${{ github.event_name != 'schedule' || (github.event_name == 'schedule' && github.repository_owner == 'ballerina-platform') }}
         uses: ballerina-platform/ballerina-library/.github/workflows/build-with-bal-test-graalvm-template.yml@main
         with:
-            lang_tag: ${{ inputs.lang_tag }}
+            lang_tag: ${{ inputs.lang_tag || '2201.10.x' }}
             lang_version: ${{ inputs.lang_version }}
             native_image_options: '-J-Xmx7G ${{ inputs.native_image_options }}'
             additional_ubuntu_build_flags: '-x :http-native:test -x :http-compiler-plugin-tests:test ${{ inputs.build_properties }}'