fix(git): fix fallback to develop branch if master not found

[mcornella]

Standards checklist:

• The PR title is descriptive.
• The PR doesn't replicate another PR which is already open.
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Changes:

• Return error code if no main or develop branch were found
• Fall back to git_develop_branch if git_main_branch was not found in gbda function

Other comments:

Fixes #11964

[carlosala]

LGTM!
It indeed fixes the issue for me.
It might be nice maybe to default to main instead of master, seems to be more common nowadays.

[LunarWatcher]

I wouldn't recommend hard switching from master to main. master is still widely used, especially in old repos. Consider checking both by default instead (which appears to already be done?)

[carlosala]

@LunarWatcher I was talking about the branch name we output if no one is found.

[mcornella]

I'd rather not over-rely on the default here and not introduce a breaking change if it's possible, so I'll merge it directly.

Thanks for the review!