Refactored database_password and solved related bugs

roles/docker-keycloak/vars/main.yml

@@ -1,6 +1,5 @@
 application_id:            "keycloak"
 database_type:            "postgres"
-database_password:        "{{applications[application_id].credentials.database_password}}"
 container_name:           "{{application_id}}_application"
 realm:                    "{{primary_domain}}"                              # This is the name of the default realm which is used by the applications
 import_directory_host:    "{{docker_compose.directories.volumes}}import/"   # Directory in which keycloack import files are placed on the host