Only apply standard swift settings on valid targets #16

Job	Run time
Cxx interop / Construct Cxx interop matrix	3s
Unit tests / Construct unit test matrix	3s
Soundness / API breakage check	1m 7s
Soundness / Documentation check	1m 17s
Soundness / Unacceptable language check	3s
Soundness / License headers check	4s
Soundness / Broken symlinks check	3s
Soundness / Format check	35s
Soundness / Shell check	30s
Soundness / Python lint check	6s
Soundness / YAML lint check	3s
Unit tests / Unit tests / Linux (5.9)	1m 9s
Unit tests / Unit tests / Linux (5.10)	1m 7s
Unit tests / Unit tests / Linux (6.0)	1m 27s
Unit tests / Unit tests / Linux (nightly-next)	1m 37s
Unit tests / Unit tests / Linux (nightly-main)	1m 36s
Cxx interop / Cxx interop / Linux (5.9)	47s
Cxx interop / Cxx interop / Linux (5.10)	49s
Cxx interop / Cxx interop / Linux (6.0)	58s
Cxx interop / Cxx interop / Linux (nightly-next)	1m 4s
Cxx interop / Cxx interop / Linux (nightly-main)	1m 5s
	15m 33s

Provide feedback