Handle macro expansion args in placeholder expansion #223

Job	Run time
Validate generated code	13s
Run tests using swift-syntax-dev-utils (Windows)	13s
Run tests using swift-syntax-dev-utils (Linux)	13s
Test / macOS (Xcode ${{ matrix.xcode_version }} - ${{ matrix.os_version }} - ${{ matrix.arch }})	0s
Test / Linux (5.9 - jammy)	12s
Test / Windows (5.9 - windows-2022)	10s
Test / Linux (5.10 - jammy)	11s
Test / Windows (6.0 - windows-2022)	15s
Test / Linux (6.0 - jammy)	12s
Test / Windows (6.1 - windows-2022)	10s
Test / Linux (6.1 - jammy)	11s
Test / Windows (nightly - windows-2019)	10s
Test / Linux (nightly-main - jammy)	13s
Test / Windows (nightly-6.1 - windows-2019)	10s
Test / Linux (nightly-6.1 - jammy)	13s
Test / Linux (nightly-6.2 - jammy)	12s
Soundness / API breakage check	0s
Soundness / Documentation check	11s
Soundness / Unacceptable language check	4s
Soundness / Broken symlinks check	4s
Soundness / Format check	11s
Soundness / License headers check	10s
Soundness / Shell check	11s
Soundness / YAML lint check	4s
Soundness / Python lint check	5s
	3m 58s

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