Bug 28879: Fix display of request metadata

Bug 28879: Fix display of request metadata

This commit adjusts the CSS surrounding the display of request
metadata, it improves the display for metadata with long key names.

Test plan:

- Do not apply patch
- Create a FreeForm ILL request with a custom metadata field with a long
  name
- View the created request
- Observe that the long metadata name breaks the display of the metadata
- Apply the patch
- View the created request
  => TEST: Observe that the display is no longer broken

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>