[SwiftParser] Handle nested '#if' in attribute list correctly #283

Job	Run time
Run tests using swift-syntax-dev-utils (Linux)	1m 47s
Validate generated code	1m 48s
Run tests using swift-syntax-dev-utils (Windows)	1m 50s
Test / Linux (6.1 - jammy)	1m 48s
Test / Linux (5.9 - jammy)	1m 48s
Test / Linux (5.10 - jammy)	1m 47s
Test / Windows (6.0 - windows-2022)	1m 51s
Test / Linux (nightly-6.2 - jammy)	1m 49s
Test / Linux (nightly-main - jammy)	1m 48s
Test / Windows (5.9 - windows-2022)	1m 53s
Test / Linux (6.0 - jammy)	1m 49s
Test / Windows (nightly-6.2 - windows-2022)	1m 50s
Test / Windows (nightly - windows-2022)	1m 51s
Test / Windows (6.1 - windows-2022)	1m 50s
Test / macOS (Xcode ${{ matrix.xcode_version }} - ${{ matrix.os_version }} - ${{ matrix.arch }})	0s
Test / Linux Static SDK Build (${{ matrix.swift_version }} - ${{ matrix.os_version }})	0s
Soundness / Documentation check	1m 47s
Soundness / YAML lint check	4s
Soundness / Python lint check	9s
Soundness / Shell check	44s
Soundness / Unacceptable language check	6s
Soundness / License headers check	10s
Soundness / Format check	39s
Test / Wasm SDK Build (${{ matrix.swift_version }} - ${{ matrix.os_version }})	0s
Soundness / Broken symlinks check	6s
Soundness / API breakage check	0s
	29m 14s

Provide feedback