refactor: make MimeMessage.get_header() return Option<&str> #6940

	name: JSON-RPC API Test

	on:
	push:
	branches: [main]
	pull_request:
	branches: [main]

	env:
	CARGO_TERM_COLOR: always
	RUST_MIN_STACK: "8388608"

	jobs:
	build_and_test:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	with:
	show-progress: false
	- name: Use Node.js 18.x
	uses: actions/setup-node@v4
	with:
	node-version: 18.x
	- name: Add Rust cache
	uses: Swatinem/rust-cache@v2
	- name: npm install
	working-directory: deltachat-jsonrpc/typescript
	run: npm install
	- name: Build TypeScript, run Rust tests, generate bindings
	working-directory: deltachat-jsonrpc/typescript
	run: npm run build
	- name: Run integration tests
	working-directory: deltachat-jsonrpc/typescript
	run: npm run test
	env:
	CHATMAIL_DOMAIN: ${{ secrets.CHATMAIL_DOMAIN }}
	- name: make sure websocket server version still builds
	working-directory: deltachat-jsonrpc
	run: cargo build --bin deltachat-jsonrpc-server --features webserver
	- name: Run linter
	working-directory: deltachat-jsonrpc/typescript
	run: npm run prettier:check

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