Merge pull request #436 from lsst/tickets/DM-45726 #543

	name: "Check commits can be merged"
	on:
	push:
	branches:
	- main
	pull_request:

	jobs:
	do-not-merge-checker:
	runs-on: ubuntu-latest

	steps:
	- name: Check that there are no commits that should not be merged
	uses: gsactions/commit-message-checker@v2
	with:
	excludeDescription: "true" # optional: this excludes the description body of a pull request
	excludeTitle: "true" # optional: this excludes the title of a pull request
	checkAllCommitMessages: "true" # optional: this checks all commits associated with a pull request
	accessToken: ${{ secrets.GITHUB_TOKEN }} # github access token is only required if checkAllCommitMessages is true
	# Check for message indicating that there is a commit that should
	# not be merged.
	pattern: ^(?!DO NOT MERGE)
	flags: "i"
	error: \|
	"This step failed because there is a commit containing the text
	'DO NOT MERGE'. Remove this commit from the branch before merging
	or change the commit summary."

	- uses: actions/checkout@v3

	- name: Check requirements.txt for branches
	shell: bash
	run: \|
	FILE=requirements.txt
	MATCH=tickets/DM-
	if grep -q $MATCH $FILE
	then
	echo "Ticket branches found in $FILE:"
	grep -n $MATCH $FILE
	exit 1
	fi

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