Improve LDAPS configuration settings

Hello Guys,

I recently posted an issue and then a suggestion to glpi  issue page on GitHub (that I resolved by my own)

Based on my previous [issue](https://github.com/glpi-project/glpi/issues/16823)

I found the "problem" but as I can't make a PR, I propose these differents solution to helps the next adminsys (and avoid him to create another issue) that will try to configure LDAPS and thinking everything is correctly configured but no.

• Not working LDAPS configuration

• Working LDAPS configuration

Why do we have to specify the protocol `ldaps://` in the `server` field when we are already setting `port` field with `636`.

Then why we don't need to specify `ldap://` when it is by default the port 389.

**I propose different fixes:**

1. Add a condition in the code that checks if the user configures port 636 but did not write ldaps:// in the server field, then a detailed error log informs the user.

1. Or Change the field description Server to something like this

1. 
   Or edit LDAP configuration interface:

- replace the port field with an LDAP / LDAPS selection button

- (depending on the choice, it will pre-fill the server field with `ldaps://` and port `636` or the default ldap and 389)

My suggestions are minimum impact and here to just improve the understanding of the admins enabling LDAPS.