[SwiftSyntax] Add #_objectFileFormat compilation conditional #121

Job	Run time
Run tests using swift-syntax-dev-utils (Windows)	54m 41s
Run tests using swift-syntax-dev-utils (Linux)	24m 36s
Validate generated code	3m 23s
Test / Windows (5.9 - windows-2022)	20m 33s
Test / Linux (5.9 - jammy)	3m 55s
Test / Windows (6.0 - windows-2022)	14m 53s
Test / Linux (5.10 - jammy)	3m 47s
Test / Windows (nightly - windows-2019)	15m 48s
Test / Linux (6.0 - jammy)	4m 4s
Test / Windows (nightly-6.1 - windows-2019)	16m 59s
Test / Linux (nightly-main - jammy)	4m 55s
Test / Linux (nightly-6.1 - jammy)	5m 2s
Soundness / API breakage check	0s
Soundness / Documentation check	1m 6s
Soundness / License headers check	11s
Soundness / Unacceptable language check	3s
Soundness / Broken symlinks check	3s
Soundness / Format check	39s
Soundness / Python lint check	6s
Soundness / Shell check	32s
Soundness / YAML lint check	6s
	2h 55m 22s

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