fix: user login and creation with LDAP (#2107)

* Corrected if statement to check if a results was returned by the LDAP search. And decoded the user_attributes from binary data to string

* removed trailing spaces

* Revert asserts in LDAP unit test back

Since an empty tuple is still a result, an user is created and the result should not be false.

* Simplified code

* Extended the LDAP implementation

* fix ldap authentication and user creation

* modified docs to include new LDAP environment variables

* update tests and linting

* add libldap-2.4-2 as runtime dependency for the api

---------

Co-authored-by: Erik Landkroon <eriklandkroon@gmail.com>

template.env

@@ -36,9 +36,14 @@ LANG=en-US
 
 # Configuration for authentication via an external LDAP server
 LDAP_AUTH_ENABLED=False
-LDAP_SERVER_URL=None
-LDAP_TLS_INSECURE=False
-LDAP_TLS_CACERTFILE=None
-LDAP_BIND_TEMPLATE=None
-LDAP_BASE_DN=None
-LDAP_ADMIN_FILTER=None
+# LDAP_SERVER_URL=""
+# LDAP_TLS_INSECURE=False
+# LDAP_TLS_CACERTFILE=
+# LDAP_BASE_DN=""
+# LDAP_QUERY_BIND=""
+# LDAP_QUERY_PASSWORD=""
+# LDAP_USER_FILTER=""
+# LDAP_ADMIN_FILTER=""
+# LDAP_ID_ATTRIBUTE=uid
+# LDAP_NAME_ATTRIBUTE=name
+# LDAP_MAIL_ATTRIBUTE=mail