If server requires LDAP signing we're getting LDAP_STRONG_AUTH_REQUIRED,
if "client ldap sasl wrapping = plain", instead of failing we now
autoupgrade to "client ldap sasl wrapping = sign" for the given connection.
Created attachment 5565 [details]
Patch for v3-5
It seems nobody wants this for 3.5.x, will be fixed in 3.6.0