docs: update master -> main in edit-links
Since the move from master to main, our "Edit on GitLab" links on docs.mesa3d.org has been pointing to the wrong branch.
Let's fix this, so we don't confuse users who want to contribute changes.
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Since the move from master to main, our "Edit on GitLab" links on docs.mesa3d.org has been pointing to the wrong branch.
Let's fix this, so we don't confuse users who want to contribute changes.