ci: Further fix to pages CI job

Follow-up to e234a4496e to remove the old
`only: main`, which was overriding the changes from that commit.

Signed-off-by: Philip Withnall <philip@tecnocode.co.uk>

.gitlab-ci.yml

@@ -661,8 +661,6 @@ scan-build:
 pages:
   extends: .only-schedules
   stage: deploy
-  only:
-    - main
   needs: ['coverage', 'style-check-advisory']
   script:
     - mv _coverage/ public/