fix wrong module configuration

etc/ds-web-service.conf.template

@@ -6,7 +6,7 @@ sslKeyFile=DM_INSTALL_DIR/etc/ssl/ds-web-service.key
 sslCaCertFile=DM_INSTALL_DIR/etc/ssl/cacert.pem
 
 [AuthorizationPrincipalManager]
-principalRetriever=dm.common.service.authentication.DbPrincipalRetriever()
+principalRetriever=DbPrincipalRetriever()
 #principalRetriever=NoOpPrincipalRetriever()
 principalAuthenticator1=CryptedPasswordPrincipalAuthenticator()
 principalAuthenticator2=LdapPasswordPrincipalAuthenticator(serverUrl='ldaps://phoebusldap.aps.anl.gov:636', dnFormat='uid=%s,ou=people,o=aps.anl.gov,dc=aps,dc=anl,dc=gov')