If refspec is a branch name, ensure that the local branch name is always
set to the refspec. In the opposite case when refspec is a commit hash,
ensure that for git repositories we always end up in the 'detached HEAD'
state.
It's also cheaper and simpler to always run `git checkout` or `hg
checkout` than it is to test if a checkout is actually needed. If the
desired refspec is already checked out then these commands are no-ops.
Signed-off-by: Paul Barker <pbarker@konsulko.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
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