[SwiftParser] Improve attribute parsing and recovering #309

Job	Run time
Run tests using swift-syntax-dev-utils (Windows)	8m 28s
Validate generated code	2m 55s
Test / Windows (6.0 - windows-2022)	8m 36s
Test / Windows (6.1 - windows-2022)	9m 9s
Test / Windows (nightly - windows-2022)	8m 34s
Run tests using swift-syntax-dev-utils (Linux)	8m 26s
Test / Windows (5.9 - windows-2022)	8m 59s
Test / Linux (5.10 - jammy)	1m 22s
Test / Swift SDK for Wasm Build (${{ matrix.swift_version }} - ${{ matrix.os_version }})	0s
Test / Linux (nightly-main - jammy)	4m 36s
Test / Linux (6.1 - jammy)	4m 0s
Test / Embedded Swift SDK for Wasm Build (${{ matrix.swift_version }} - ${{ matrix.os_version }})	0s
Test / Linux (nightly-6.2 - jammy)	4m 50s
Test / Linux (5.9 - jammy)	1m 25s
Test / Static Linux Swift SDK Build (${{ matrix.swift_version }} - ${{ matrix.os_version }})	0s
Test / Linux (6.0 - jammy)	1m 29s
Test / Windows (nightly-6.2 - windows-2022)	8m 27s
Test / macOS (Xcode ${{ matrix.xcode_version }} - ${{ matrix.os_version }} - ${{ matrix.arch }})	0s
Soundness / Documentation check	4m 6s
Soundness / Unacceptable language check	4s
Soundness / License headers check	14s
Soundness / Format check	35s
Soundness / Shell check	34s
Soundness / YAML lint check	6s
Soundness / Python lint check	6s
Soundness / Broken symlinks check	4s
Soundness / API breakage check	0s
	1h 27m 5s

Provide feedback