ci: Bump Go to 1.21, refresh actions #479

	# NOTE: This name appears in GitHub's Checks API and in workflow's status badge.
	name: ci-verify-update

	# Trigger the workflow when:
	on:
	# Or when a pull request event occurs for a pull request against one of the
	# matched branches.
	pull_request:
	branches:
	- production

	jobs:
	verify-update:
	# NOTE: This name appears in GitHub's Checks API.
	name: verify-update
	runs-on: ubuntu-latest
	steps:
	- name: Checkout base registry
	uses: actions/checkout@v4
	with:
	ref: ${{ github.base_ref }}
	path: snapshot-base
	- name: Checkout updated registry
	uses: actions/checkout@v4
	with:
	# Check out pull request's HEAD commit instead of the merge commit to
	# work-around an issue where wrong a commit is being checked out.
	# For more details, see:
	# https://github.com/actions/checkout/issues/299.
	ref: ${{ github.event.pull_request.head.sha }}
	path: snapshot-updated
	- name: Set up Go
	uses: actions/setup-go@v5
	with:
	go-version: "1.21.x"
	- name: Install latest metadata-registry-tools
	run: \|
	go install github.com/oasisprotocol/metadata-registry-tools/oasis-registry@latest
	- name: Verify update
	run: \|
	cd snapshot-updated
	oasis-registry verify --update ../snapshot-base

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