Starting with 8.5.8, we are merging the signed upstream tags as
upstream, instead of using the tarball that doesn’t ship tests.

# Example to import upstream 8.5.9 version
version=8.5.9
# We still use the upstream branch to drop the .gitattributes file from upstream
gbp import-ref --upstream-tag=%\(version%~%-\)s -u$version --debian-branch=upstream-bullseye
gbp import-ref --upstream-tree=BRANCH -u$version
