[Feature] push and or commit input

[nbrugger-tgm]

I think there are plenty of reasons why you do not want this action to commit or push the file, like adding the changelog to a github-release or posting the changelog into a comment in a PR or issue.

Proposed inputs

push: if false the commited changes wont be pushed (default: true)
commit: if false changes wont be commited (default: true)

[woile]

Sounds good! If you want to send a PR I'd be thankful. Otherwise next week I'll include it

[nbrugger-tgm]

Implemented in #16