Add Swift package index yml file #230

Job	Run time
Test / Windows (5.9 - windows-2022)	9m 33s
Test / Linux (5.8 - jammy)	1m 58s
Test / Windows (6.0 - windows-2022)	8m 36s
Test / Linux (5.9 - jammy)	2m 12s
Test / Windows (nightly - windows-2019)	11m 28s
Test / Linux (5.10 - jammy)	2m 9s
Test / Windows (nightly-6.0 - windows-2019)	9m 2s
Test / Linux (6.0 - jammy)	2m 21s
Test / Linux (nightly-main - jammy)	4m 1s
Test / Linux (nightly-6.0 - jammy)	3m 2s
Soundness / API breakage check	3m 17s
Soundness / Documentation check	2m 23s
Soundness / Unacceptable language check	4s
Soundness / License headers check	0s
Soundness / Broken symlinks check	3s
Soundness / Format check	33s
Soundness / Shell check	34s
Soundness / YAML lint check	2s
Soundness / Python lint check	6s
	1h 1m 24s

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