[6.2] Parse @unsafe nonisolated conformance #276

Job	Run time
Validate generated code	2m 57s
Run tests using swift-syntax-dev-utils (Linux)	24m 12s
Run tests using swift-syntax-dev-utils (Windows)	39m 49s
Test / Linux (5.10 - jammy)	3m 53s
Test / Linux (6.0 - jammy)	4m 1s
Test / Linux (6.1 - jammy)	3m 56s
Test / Linux (nightly-6.2 - jammy)	4m 54s
Test / Linux (5.9 - jammy)	3m 54s
Test / Windows (6.0 - windows-2022)	12m 57s
Test / Windows (6.1 - windows-2022)	13m 30s
Test / Linux (nightly-main - jammy)	4m 38s
Test / Windows (nightly-6.2 - windows-2022)	17m 43s
Test / Windows (5.9 - windows-2022)	17m 44s
Test / Windows (nightly - windows-2022)	16m 3s
Test / macOS (Xcode ${{ matrix.xcode_version }} - ${{ matrix.os_version }} - ${{ matrix.arch }})	0s
Soundness / Documentation check	4m 59s
Soundness / License headers check	10s
Soundness / Unacceptable language check	4s
Soundness / API breakage check	0s
Soundness / Broken symlinks check	5s
Soundness / Format check	43s
Soundness / Shell check	41s
Soundness / YAML lint check	7s
Soundness / Python lint check	7s
	2h 57m 7s

Provide feedback