fixup! DB: Soubor s diplomy si pamatuje, zda je schválen

mo/db.py

@@ -1167,7 +1167,8 @@ class Certificate(Base):
     cert_set = relationship('CertSet')
     cert_file = relationship('CertFile',
                              primaryjoin='and_(CertFile.cert_set_id == Certificate.cert_set_id, CertFile.type == Certificate.type)',
-                             foreign_keys='[Certificate.cert_set_id, Certificate.type]')
+                             foreign_keys='[Certificate.cert_set_id, Certificate.type]',
+                             viewonly=True)
     user = relationship('User')