ExternalProject: Fix misleading git update output
When re-running the build with the git download method,
and where GIT_TAG is set to a tag name that we already have
locally from the first run, the second run will skip the update
step if it is already at the requested tag. The message in this
case was previously printing the commit hash instead of the
tag name, which was wrong. This wasn't noticed before
because that output wasn't usually shown, but we now do
show that message after making message output log levels
more consistent between the steps.
1 file changed
