Quote ldap uri

python-ldap in Bullseye fails to parse the file path unless it is quoted:

>>> a = ldapurl.LDAPUrl('ldapi://%2fvar%2ffoo')
>>> a.hostport
'/var/foo'
>>> a = ldapurl.LDAPUrl('ldapi:///var/foo')
>>> a.hostport
''

cc ai3/prod#214

ai_webdav_auth/auth_server.py

@@ -39,7 +39,7 @@ from io import TextIOWrapper
 SO_PEERCRED = 17
 
 # Default LDAP URI.
-LDAP_DEFAULT_URI = 'ldapi:///var/run/ldap/ldapi'
+LDAP_DEFAULT_URI = 'ldapi://%2fvar%2frun%2fldap%2fldapi'
 
 # LDAP base UID.
 LDAP_DEFAULT_BASE_UID = 'ou=People, dc=investici, dc=org, o=Anarchy'