Fix DB name in MongStore::copyDB
Fix DB name in MongStore::copyDB

Mongo uses the admin DB to handle DB copies
sil-student-projects/web-languageforge,sil-student-projects/web-languageforge,sillsdev/web-cat,sillsdev/web-cat,sil-student-projects/web-languageforge,sil-student-projects/web-languageforge,sillsdev/web-scriptureforge,sil-student-projects/web-languageforge,sillsdev/web-cat,sillsdev/web-cat,ermshiperete/web-languageforge,ermshiperete/web-languageforge,sillsdev/web-scriptureforge,ermshiperete/web-languageforge,ermshiperete/web-languageforge,sillsdev/web-cat,sillsdev/web-cat,sil-student-projects/web-languageforge,sillsdev/web-cat,ermshiperete/web-languageforge,ermshiperete/web-languageforge,ermshiperete/web-languageforge,sil-student-projects/web-languageforge,sillsdev/web-scriptureforge,sillsdev/web-scriptureforge,sillsdev/web-scriptureforge,ermshiperete/web-languageforge,sillsdev/web-scriptureforge,sillsdev/web-cat,sillsdev/web-scriptureforge,sil-student-projects/web-languageforge,sillsdev/web-scriptureforge