molecule: add namespace to meta/main.yml

fixed:
ERROR    Computed fully qualified role name of postgresql_cluster does not follow current galaxy requirements.
Please edit meta/main.yml and assure we can correctly determine full role name:

galaxy_info:
role_name: my_name  # if absent directory name hosting role is used instead
namespace: my_galaxy_namespace  # if absent, author is used instead

Author: vitabaks

meta/main.yml

@@ -1,7 +1,8 @@
 ---
 galaxy_info:
   role_name: postgresql_cluster
-  description: PostgreSQL High-Availability Cluster (based on Patroni).
+  description: PostgreSQL High-Availability Cluster (based on Patroni)
+  namespace: vitabaks
   author: Vitaliy Kukharik ([email protected])
   license: MIT