Reset password

Do not allow to change LDAP password

To test 
* Use the first user listed under https://www.openmicroscopy.org/site/team/Password
* Check that the LDAP info are displayed and you cannot change the password
* Log out
* log in as an admin
* Go to the Admin tab
* Expand Test Group and select the user used previously
* Check that the LDAP info are displayed. Check that you can neither modify the password  nor the login name.
This is not necessary. PR https://github.com/openmicroscopy/openmicroscopy/pull/3119 adds flag on Experimenter obejct. You may want to hold that PR until is merged and then use the flag rather then extra call