clang-tidy.yml: updated to Clang 21 (#421) #2

	# Syntax reference https://help.github.com/en/actions/reference/workflow-syntax-for-github-actions
	# Environment reference https://help.github.com/en/actions/reference/virtual-environments-for-github-hosted-runners
	name: format

	on:
	push:
	branches:
	- 'master'
	- 'releases/**'
	- '1.*'
	tags:
	- '1.*'
	pull_request:

	permissions:
	contents: read

	jobs:
	format:

	runs-on: ubuntu-22.04

	defaults:
	run:
	shell: bash -euo pipefail {0}

	env:
	UNCRUSTIFY_INSTALL_DIR: ${{ github.workspace }}/runformat-uncrustify

	steps:
	- uses: actions/checkout@v5
	with:
	persist-credentials: false

	- name: Determine uncrustify version
	id: get-uncrustify-version
	run: \|
	version="$(./runformat --expected-uncrustify-version)"
	echo "Expected uncrustify version: $version"
	echo "version=$version" >> "$GITHUB_OUTPUT"

	- name: Set UNCRUSTIFY_VERSION env variable
	run: \|
	version=$(./runformat --expected-uncrustify-version)
	echo "version [$version]"
	echo "UNCRUSTIFY_VERSION=${version}" >> "$GITHUB_ENV"

	- name: Cache uncrustify
	uses: actions/cache@v4
	id: cache-uncrustify
	with:
	path: ${{ env.UNCRUSTIFY_INSTALL_DIR }}
	key: ${{ runner.os }}-uncrustify-${{ steps.get-uncrustify-version.outputs.version }}

	- name: Install uncrustify
	if: steps.cache-uncrustify.outputs.cache-hit != 'true'
	run: \|
	./runformat --install --install-dir "${UNCRUSTIFY_INSTALL_DIR}"

	- name: Uncrustify check
	run: \|
	./runformat

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