Removes bogus UNO command AcceptChange and RejectChange

These are not real commands. The real ones are:
- AcceptTracedChange
- RejectTracedChange

Change-Id: I352cea4a5ffec73947932264783b61ae044f25cf
Signed-off-by: Rodolfo Ribeiro Gomes <rodolforg@gmail.com>
Reviewed-on: https://gerrit.libreoffice.org/8000
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>