Unable to enable Pipelines without administrative access (BBCI-3240)

Summary

Users find themselves trying to enable Pipelines inside repositories that they have access but after pressing the "Enable pipelines" button nothing happens, the snipper appears and never stops. This is happening because the user does not have administrative access to the repository, only users with admin access can enable Pipelines.

Steps to Reproduce

1. Access a repository w/o administrative access.
2. Click Pipelines under the "Navigation" menu at the sidebar on the left.
3. Press the "Enable Pipelines" option.

Expected Results

A warning message show appear and inform the user that he can't enable Pipelines because he don't have permission and should contact the repository admin.

Actual Results

The user clicks "Enable pipelines" and nothing happens, the snipper appears and never goes away. No messages appear to inform the user why/what went wrong.