Update mdoc to 2.4.0 (#1275) #1243

Job	Run time
bincompat	6m 12s
examples (ubuntu-latest)	4m 8s
integration-tests (ubuntu-20.04)	44m 23s
examples (windows-latest)	6m 49s
test (ubuntu-latest, 8, 2.12.17)	4m 16s
integration-tests (macos-latest)	51m 28s
format	25s
integration-tests (windows-latest)	38m 47s
test (ubuntu-latest, 8, 2.12.18)	3m 26s
publishLocal	16m 22s
test (ubuntu-latest, 8, 2.13.11)	3m 38s
website	2m 7s
test (ubuntu-latest, 8, 2.13.12)	3m 32s
test (ubuntu-latest, 8, 3.3.0)	4m 7s
test (windows-latest, 8, 2.13.12)	5m 58s
test (macos-latest, 8, 2.13.12)	5m 18s
test (ubuntu-latest, 17, 2.12.18)	4m 50s
all-tests	2s
	3h 25m 48s

Provide feedback