Bug 10474: Translate some English strings in German sample notices

Bug 10474: Translate some English strings in German sample notices

This translates 2 strings missed doing the initial translation in
ISSUESLIP.

To test:
- Run the web installer in German.
Altnernatively:
- Truncate your letters table and run the SQL against the database.

Check that the notices were added correctly, especially ISSUESLIP.

Signed-off-by: Chris Cormack <chris@bigballofwax.co.nz>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>
(cherry picked from commit aecb163f69b238314bbd67215ce2d8950aeab060)
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>