Version of the Action
v4.1.0

Describe the bug
The push when no branch is specified just doesn't make it back to Github in V4.1.0 while it does work in v3.0.0

To Reproduce
Steps to reproduce the behaviour:

1. Using v4.1.0 I expect after the commit the push back to the originating branch to occur. Instead I get an "everything is up to date" message.
   https://github.com/TSSF-Asia-Pacific/communityobedience/runs/506933775?check_suite_focus=true#step:4:21

Expected behaviour
Instead of everything is up to date, it should show that it pushed back to the branch, like it does in v3.0.0
https://github.com/TSSF-Asia-Pacific/communityobedience/runs/506938310?check_suite_focus=true#step:5:19