Merge pull request #336 from opf/fix/merge-upstream-workflow

`script/merge-upstream` workflow fixes

Author: HDinger

.gitattributes

@@ -3,4 +3,3 @@ Gemfile.lock merge=ours
 demo/Gemfile.lock merge=ours
 lib/primer/view_components/version.rb merge=ours
 package-lock.json merge=ours
-package.json merge=ours

script/merge-upstream

@@ -21,6 +21,8 @@ git reset --hard origin/main
 git merge bump/primer-upstream-ref --no-commit
 
 find .changeset/ -name "*.md" -exec $SED -i "s/\@primer\/view-components/\@openproject\/primer-view-components/g" {} +
-
 git add .changeset/
+
+./setup
+git add */Gemfile.lock */package-lock.json
 git commit