Bug 30008: (bug 29690 follow-up) Fix Invalid data, cannot decode metadata object

Bug 30008: (bug 29690 follow-up) Fix Invalid data, cannot decode metadata object

Test plan:
1 - Find a record in the staff catalog
2 - Edit the record
3 - In the 520 notes field, add an ASCII escape character (27 decimal, 1b hex)
    On ubuntu Ctrl+Shift+u, then 1b, enter
4 - Save the record
5 - Set syspref ShowComponentRecords to 'both...'
6 - On record details: New->New child record
7 - Save the record
8 - Attempt to view the parent record in the staff client and opac

Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>