fixes #5224 - Don't update a user with blank LDAP attribute values
(cherry picked from commit 2fe12e2c5f011d68cb4afbf3cd5e070e1af36155)
fixes #5224 - Don't update a user with blank LDAP attribute values
(cherry picked from commit 2fe12e2c5f011d68cb4afbf3cd5e070e1af36155)