Ignoring statuses of synched files under vendor when publishing

[khanism]

Regarding issue #200
This change adds some options to the check of the repository when publishing your Buffrs project.

When publishing, the statuses of the synched *.proto files under vendor are not included, avoiding the project being dirty as described in the issue

[mara-schulke]

Hi @khanism, thank you for contributing!

Have you seen the work on #217 / 78740b1 ?

I think this issue still exists, but the way we check statuses for git has been changed 😊

If you can rebase and update your implementation I am more than happy to merge this, tysm!

[khanism]

@mara-schulke sorry for the long time of funkstille. Thanks for the remark, I'll update this so we can proceed with this PR :)

[khanism]

Closing because of updated fix in #263