How to grab Grafana LDAP Login creds from the login form

I have been able to follow the LDAP configuration guide from Grafana and successfully login using the creds. But I have one problem. In the config file bind_password for one ldap user has to be saved (as env var or however). I want to be able to take the password entered in the login form to query the ldap server without having a bin_password at all in the ldap.toml file.
Similar to using %s for email address or username is it possible to have a %p or something else for the password field as well?