upgrade syn to 2.0 and clap to 4.0 #32

	name: ci

	on:
	push:
	branches:
	- main
	workflow_dispatch:
	inputs:
	tmate_debug:
	description: 'Run tmate for debugging'
	type: boolean
	required: false
	default: false

	jobs:
	ci:
	strategy:
	fail-fast: false
	matrix:
	os: [ubuntu-22.04]

	runs-on: ${{ matrix.os }}

	steps:
	- name: bazel cache
	uses: actions/cache@v2
	with:
	path: \|
	~/.cache/bazelisk
	~/.cache/bazel
	key: ${{ runner.os }}-${{ github.ref }}

	- name: checkout
	uses: actions/checkout@v2

	- name: tmate debugging
	uses: mxschmitt/action-tmate@v3
	with:
	limit-access-to-actor: true
	if: ${{ github.event_name == 'workflow_dispatch' && github.event.inputs.tmate_debug && always() }}

	- name: build and test
	run: bazel test //... --config ci

	- name: test gazelle invariance
	run: bazel run //:gazelle -- --mode=diff --strict

	- name: build and test for example
	run: bazel test //...
	working-directory: ./example

	- name: test gazelle invariance for example
	run: bazel run //:gazelle -- --mode=diff --strict
	working-directory: ./example

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