do not quote %(user)s in dav filter

debian/ai-auth-server.conf

@@ -18,7 +18,7 @@ LDAP_SERVICE_MAP = {
     # DAV access (webdav fcgi handler).
     'dav': {
         'base': 'ou=People, dc=investici, dc=org, o=Anarchy',
-        'filter': '(&(objectClass=ftpAccount)(status=active)(host=%(shard)s)(ftpname=%%(user)s))' % host,
+        'filter': '(&(objectClass=ftpAccount)(status=active)(host=%(shard)s)(ftpname=%(user)s)',
     },
 
     # Main account (pannello).