Tests

[ENH] Extend `Extension` class test suite #1774

Job	Run time
docker	4s
(ubuntu-latest, Py3.8, sk0.23.1, sk-only:false)	4s
(windows-latest, Py, sk0.24.*, sk-only:false)	4s
(ubuntu-latest,Py3.12,sk1.4.*,sk-only:true)	1m 6s
(ubuntu-latest,Py3.10,sk1.5.*,sk-only:true)	56s
(ubuntu-latest,Py3.10,sk1.7.*,sk-only:true)	1m 2s
(ubuntu-latest,Py3.11,sk1.4.*,sk-only:true)	56s
(ubuntu-latest,Py3.12,sk1.3.*,sk-only:true)	1m 2s
(ubuntu-latest,Py3.10,sk1.3.*,sk-only:true)	55s
(ubuntu-latest,Py3.12,sk1.7.*,sk-only:true)	59s
(ubuntu-latest,Py3.13,sk1.6.*,sk-only:true)	1m 4s
(ubuntu-latest,Py3.10,sk1.4.*,sk-only:true)	54s
(ubuntu-latest,Py3.14,sk1.7.*,sk-only:true)	1m 7s
(ubuntu-latest,Py3.14,sk1.5.*,sk-only:true)	4m 14s
(ubuntu-latest,Py3.11,sk1.3.*,sk-only:true)	57s
(ubuntu-latest,Py3.11,sk1.5.*,sk-only:true)	59s
(ubuntu-latest,Py3.12,sk1.5.*,sk-only:true)	1m 2s
(ubuntu-latest,Py3.13,sk1.7.*,sk-only:true)	1m 0s
(ubuntu-latest,Py3.12,sk1.5.*,sk-only:false)	14m 55s
(ubuntu-latest,Py3.11,sk1.6.*,sk-only:true)	1m 5s
(ubuntu-latest,Py3.14,sk1.6.*,sk-only:true)	4m 12s
(ubuntu-latest,Py3.11,sk1.7.*,sk-only:true)	57s
(ubuntu-latest,Py3.12,sk1.6.*,sk-only:true)	1m 7s
(ubuntu-latest,Py3.13,sk1.5.*,sk-only:true)	1m 4s
(windows-latest,Py3.12,sk1.5.*,sk-only:false)	4m 48s
(ubuntu-latest,Py3.14,sk1.7.*,sk-only:false)	2m 59s
(ubuntu-latest,Py3.10,sk1.6.*,sk-only:true)	1m 2s
	50m 34s

Provide feedback