Merge upstream branches #19776

	# .github/workflows/example.yml

	name: Merge upstream branches
	on:
	schedule:
	# actually, ~5 minutes is the highest
	# effective frequency you will get
	- cron: '* * * * *'
	jobs:
	merge:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4
	- name: Merge upstream
	run: \|
	git config --global user.name 'your-name'
	git config --global user.email '[email protected]'

	# "git checkout master" is unnecessary, already here by default
	git pull --unshallow # this option is very important, you would get
	# complains about unrelated histories without it.
	# (but actions/checkout@v2 can also be instructed
	# to fetch all git depth right from the start)

	git remote add upstream https://github.com/example/test.git
	git fetch upstream

	# Neither forget the -b opt,
	# the feature/x ref is ambiguous at this stage
	git checkout -b feature/x origin/feature/x
	git merge --no-edit upstream/feature/x
	git push origin feature/x

	git checkout master
	git merge --no-edit upstream/master
	git push origin master

	# etc

Provide feedback