Bug 6379: Remove link from unapproved tags

Bug 6379: Remove link from unapproved tags

At the OPAC, if the tag is not approved, the tag's link did not return
any result.

This patch removes the link.
Test plan:
1/ Set TagsModeration to 'Require'
2/ Create tags at the OPAC
3/ Approve a couple
4/ Confirm that unapproved tags does not have links.

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
works as described, no errors

For the (approved) link to work I need to install YAML::XS

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>