Support submodule cloning option

[emakryo]

Currently, there is no way to set gitSumobuleConfigOverride in this action.
https://docs.aws.amazon.com/codebuild/latest/APIReference/API_StartBuild.html#CodeBuild-StartBuild-request-gitSubmodulesConfigOverride

This would be helpful when the repository is private.

[pshiko]

I've tried creating a fork repository with gitSumobuleConfigOverride set and tried fetching submodules, but submodules fetching private repositories didn't work due to permission error.

https://github.com/pshiko/aws-codebuild-run-build

Does codebuild not support submodule fetching of private repositories?

[taoyong-ty]

Could you check if the access token you provided to CodeBuild has the required permission to download the submodule? https://docs.aws.amazon.com/codebuild/latest/userguide/access-tokens.html