SQ??? ldb_mdb/tests: Run api and index test also on lmdb WHY not the same dict for...

SQ??? ldb_mdb/tests: Run api and index test also on lmdb WHY not the same dict for all tests?  ldb: Allow tests to operate on ldb_mdb after new restrictions

The tests were working fine on ldb_mdb but only in the mode without
the GUID index.  This mode is not OK for production so has been banned
but this means we need to rework the tests to set an objectGUID on
each record.

Signed-off-by: Gary Lockyer <gary@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>