use 2.1 branch of FTRepo for 2.1.0

[tianleh]

Signed-off-by: Tianle Huang [email protected]

Description

The FTRepo will follow the Core branching strategy. https://github.com/opensearch-project/.github/blob/main/RELEASING.md#opensearch-branching This is current 2.1 branch https://github.com/opensearch-project/opensearch-dashboards-functional-test/tree/2.1 Later we will update main branch of FTRepo to be 3.0

Issues Resolved

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[tianleh]

* What went wrong:
Project 'plugin' not found in root project 'opensearch-sql'.

* Try:
> 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.

* Get more help at https://help.gradle.org

BUILD FAILED in 796ms
2022-07-04 04:23:34 ERROR    CI Manifest check failed
Traceback (most recent call last):
  File "./src/run_ci.py", line 25, in <module>
    sys.exit(main())
  File "./src/run_ci.py", line 20, in main
    CiManifests.from_file(args.manifest, args).check()
  File "/usr/share/opensearch/workspace/opensearch-build/src/ci_workflow/ci_manifest.py", line 21, in check
    self.__check__()
  File "/usr/share/opensearch/workspace/opensearch-build/src/ci_workflow/ci_input_manifest.py", line 41, in __check__
    ci_check_list.check()
  File "/usr/share/opensearch/workspace/opensearch-build/src/ci_workflow/ci_check_list_source.py", line 43, in check
    instance = klass(self.component, self.git_repo, self.target, check.args)
  File "/usr/share/opensearch/workspace/opensearch-build/src/ci_workflow/ci_check_gradle_dependencies.py", line 22, in __init__
    self.dependencies = self.__get_dependencies()
  File "/usr/share/opensearch/workspace/opensearch-build/src/ci_workflow/ci_check_gradle_dependencies.py", line 39, in __get_dependencies
    lines = self.git_repo.output(cmd)
  File "/usr/share/opensearch/workspace/opensearch-build/src/git/git_repository.py", line 78, in output
    return subprocess.check_output(command, cwd=cwd, shell=True).decode().strip()
  File "/usr/local/lib/python3.7/subprocess.py", line 411, in check_output
    **kwargs).stdout
  File "/usr/local/lib/python3.7/subprocess.py", line 512, in run
    output=stdout, stderr=stderr)
subprocess.CalledProcessError: Command './gradlew plugin:dependencies -Dopensearch.version=2.1.0-SNAPSHOT -Dbuild.snapshot=true --configuration compileOnly | grep -e "---"' returned non-zero exit status 1.

[tianleh]

The error above is reported in #2294 which is unrelated to changes in this PR.