No force-pushing when there are no updates

[jonathanloske]

It would be nice if a commit/branch could stay untouched if there are no changes to it.

Current behavior Whenever git review is run, there is a force-push for all commits/branches, no matter if there were any changes or not. This creates unnecessary overhead as it triggers pipelines and creates visual clutter.

For example, if git review is run twice in a row, all affected commits/branches will be force-pushed twice.

Desired behavior git review only touches branches if there are any changes in them, ie fixups.