Bump actions/checkout from 6 to 7 #18

Job	Run time
test (ubuntu-latest, 28.2, false)	35s
test (ubuntu-latest, 27.2, false)	39s
test (macos-latest, 30.1, false)	2m 50s
test (macos-latest, 29.4, false)	2m 39s
test (ubuntu-latest, snapshot, true)	30s
test (windows-latest, 28.2, false)	54s
test (windows-latest, 27.2, false)	1m 5s
test (macos-latest, 28.2, false)	2m 54s
test (macos-latest, snapshot, true)	2m 59s
test (windows-latest, 29.4, false)	1m 23s
test (windows-latest, snapshot, true)	1m 4s
test (windows-latest, 26.3, false)	1m 11s
test (ubuntu-latest, 29.4, false)	36s
test (windows-latest, 30.1, false)	1m 16s
test (ubuntu-latest, 30.1, false)	32s
test (ubuntu-latest, 26.3, false)	35s
	21m 42s

Provide feedback