Bug 32023: Remove hr in OpacNav for CMS pages

Bug 32023: Remove hr in OpacNav for CMS pages

In a page created with the new Pages tool, there is a
<hr> above the OpacNav block.
This hr is not present on other OPAC pages and is
removed by this patch.

To test:
1. Go to Tools > Pages > New entry
2. Create a page and save
3. Copy the OPAC link
4. Go to Tools > HTML customizations > New entry
5. Create an OpacNav entry with the link to the page
6. Go to the OPAC main page
   --> Notice how the left navigation section looks
7. Click on the link on the left to go to the page
   --> an horizontal line appears above OpacNav
8. Apply patch
9. Repeat test - the horizontal line should be gone now

Signed-off-by: Caroline Cyr La Rose <caroline.cyr-la-rose@inlibro.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>