Add support for SE-0460 @specialized #209

Job	Run time
Validate generated code	2m 49s
Run tests using swift-syntax-dev-utils (Windows)	47m 3s
Run tests using swift-syntax-dev-utils (Linux)	23m 23s
Test / Linux (5.9 - jammy)	3m 52s
Test / macOS (Xcode ${{ matrix.xcode_version }} - ${{ matrix.os_version }} - ${{ matrix.arch }})	0s
Test / Windows (5.9 - windows-2022)	26m 6s
Test / Linux (5.10 - jammy)	3m 48s
Test / Windows (6.0 - windows-2022)	14m 49s
Test / Linux (6.0 - jammy)	4m 8s
Test / Windows (6.1 - windows-2022)	19m 3s
Test / Linux (6.1 - jammy)	3m 52s
Test / Windows (nightly - windows-2019)	15m 37s
Test / Linux (nightly-main - jammy)	4m 41s
Test / Windows (nightly-6.1 - windows-2019)	15m 27s
Test / Linux (nightly-6.1 - jammy)	4m 53s
Soundness / API breakage check	0s
Soundness / Broken symlinks check	4s
Soundness / Documentation check	5m 9s
Soundness / Format check	37s
Soundness / License headers check	9s
Soundness / Python lint check	7s
Soundness / Shell check	32s
Soundness / Unacceptable language check	3s
Soundness / YAML lint check	3s
	3h 16m 15s

Provide feedback