.github: Bump actions/checkout from 3 to 4 #139

	name: buf

	on:
	push:
	branches: [ main ]
	pull_request:

	jobs:
	validate:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: bufbuild/buf-setup-action@v1
	- uses: bufbuild/buf-lint-action@v1
	with:
	input: 'proto'

	# We need to fetch main so we can compare breaking changes against whatever is in main right now.
	- name: Fetch origin/main
	run: git fetch --no-tags --prune --depth=1 origin +refs/heads/main:refs/remotes/origin/main

	- uses: bufbuild/buf-breaking-action@v1
	with:
	input: 'proto'
	against: '.git#branch=origin/main,subdir=proto'

	# Push buf module to the buf schema registry, but only if the validate action succeeded and if the action is running
	# on branch main.
	push:
	runs-on: ubuntu-latest
	needs: validate
	if: ${{ github.ref == 'refs/heads/main' }}
	steps:
	- uses: actions/checkout@v4
	- uses: bufbuild/buf-setup-action@v1
	- uses: bufbuild/buf-push-action@v1
	with:
	input: 'proto'
	buf_token: ${{ secrets.BUF_TOKEN }}

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