Fixes an issue with platforms definition in $expid/conf when you're using advanced configuration

This merge fixes #1129 (closed).

• Changed a raise Exception per raise AutosubmitCritical at the moment of loading platforms.
• This exception will now be a warning when encountered during the create/refresh process. This only disables remote git cloning and defaults to the local platform. ( that should be already the expected behaviour but didn't work as expected )

Git remote cloning is a feature that allows the cloning of the repository to a remote folder. I believe it is not used as often people just create a local setup / remote setup/ sync job ...