[Parser] Always enable `abiAttribute` feature #133

Job	Run time
Run tests using swift-syntax-dev-utils (Linux)	23m 7s
Run tests using swift-syntax-dev-utils (Windows)	44m 9s
Validate generated code	2m 49s
Test / Linux (5.9 - jammy)	3m 53s
Test / Windows (5.9 - windows-2022)	23m 27s
Test / Linux (5.10 - jammy)	3m 49s
Test / Windows (6.0 - windows-2022)	18m 44s
Test / Linux (6.0 - jammy)	4m 1s
Test / Windows (nightly - windows-2019)	16m 32s
Test / Windows (nightly-6.1 - windows-2019)	16m 18s
Test / Linux (nightly-main - jammy)	4m 44s
Test / Linux (nightly-6.1 - jammy)	4m 32s
Soundness / API breakage check	0s
Soundness / Broken symlinks check	3s
Soundness / Documentation check	4m 50s
Soundness / License headers check	10s
Soundness / Unacceptable language check	4s
Soundness / Format check	37s
Soundness / Python lint check	8s
Soundness / Shell check	39s
Soundness / YAML lint check	6s
	2h 52m 42s

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