Add and enable preview_link module ( and confirm it works )

[finnlewis]

Coming from localgovdrupal/localgov_microsites_project#63 (comment)

We added preview_link to the localgov profile, but not to the localgov_microsites profile.

This issue is to add, enable and test that it works.

This should help fix the errors on https://github.com/localgovdrupal/localgov_microsites_project/actions/runs/10331191810/job/28601123882?pr=63#step:4:16

[dedavidson]

We have added this for a council but after testing (and debugging) there appears to be a conflict between the access methods of preview_link and domains.