Drop Swift 5.9 #29

Job	Run time
Cxx interop / Construct Cxx interop matrix	5s
Unit tests / Construct unit test matrix	3s
Soundness / Documentation check	3m 4s
Soundness / Format check	30s
Soundness / Broken symlinks check	4s
Soundness / API breakage check	4m 37s
Soundness / License headers check	4s
Soundness / Unacceptable language check	3s
Soundness / Python lint check	5s
Soundness / Shell check	30s
Soundness / YAML lint check	3s
Cxx interop / Swift 6 language mode	2m 51s
Static SDK / Static SDK / Linux (latest-release Jammy)	3m 41s
Static SDK / Static SDK / Linux (main Jammy)	2m 20s
Unit tests / Unit tests / Linux (5.9)	23s
Unit tests / Unit tests / Linux (5.10)	2m 29s
Unit tests / Unit tests / Linux (6.0)	3m 3s
Unit tests / Unit tests / Linux (6.1)	2m 59s
Unit tests / Unit tests / Linux (nightly-next)	3m 39s
Unit tests / Unit tests / Linux (nightly-main)	1m 26s
Cxx interop / Cxx interop / Linux (5.9)	34s
Cxx interop / Cxx interop / Linux (5.10)	2m 37s
Cxx interop / Cxx interop / Linux (6.0)	3m 5s
Cxx interop / Cxx interop / Linux (6.1)	3m 0s
Cxx interop / Cxx interop / Linux (nightly-next)	3m 44s
Cxx interop / Cxx interop / Linux (nightly-main)	1m 29s
	46m 28s

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