[BUG] Automatic main tag release causes warning: refname 'main' is ambiguous

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What is the bug?

We have a main tag that makes the refname main ambigous.

How can one reproduce the bug?

For example, trying to pull someone else's changes in to test.

git checkout -b new-branch main

warning: refname 'main' is ambiguous.
fatal: ambiguous object name: 'main'

You can work around this locally.

$ git tag -d main
Deleted tag 'main' (was c58908d)

What is the expected behavior?

Main should be unambiguous.