Updated 184 broken links to handbook index

After the handbook was split into smaller pages by !4939 many of the old links needed updating
4 jobs for jej-fix-broken-handbook-links in 12 minutes and 25 seconds (queued for 7 seconds)
Status Job ID Name Coverage
  Build
passed #10395741
gitlab-org
build_branch

00:11:56

passed #10395737
gitlab-org
lint

00:03:23

 
  Deploy
passed #10395742
deploy review-apps allowed to fail
review

00:00:26

passed #10395743
deploy review-apps manual
review_stop

00:00:00