doc: Clarify that the timeout is in seconds

7 jobs for wip/doc in 8 minutes and 13 seconds
Status Name Job ID Coverage
  Build
passed build:native-debian-bullseye:full #374452
librem5

00:02:18

passed build:native-debian-bullseye:lib #374453
librem5

00:00:47

 
  Test
passed test:native-debian-bullseye #374454
librem5

00:02:30

62.4%
 
  Package
passed package-debian-bullseye #374455
librem5

00:00:48

passed package-debian-bullseye:arm64 #374456
librem5:arm64

00:03:23

 
  Test Package
passed autopkgtest-debian-bullseye-package #374457
librem5

00:01:26

passed lintian-debian-bullseye-package #374458
librem5

00:00:31