Add ApplicationSetting for the `git_push_create_all_pipelines` feature flag

What does this MR do and why?

Add ApplicationSetting for the git_push_create_all_pipelines feature flag

This allows instances to set a way to change the limit of creating a maximum of 4 git pipelines per push

References

• Convert feature flag `git_push_create_all_pipel... (#350886 - closed)

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