fix(python.sls): fix salt-lint errors

```bash
Examining postgres/python.sls of type state
[206] Jinja variables should have spaces before and after: {{ var_name }}
postgres/python.sls:8
    - name: {{ postgres.pkg_python}}
```

postgres/python.sls

@@ -5,7 +5,7 @@ include:
 
 postgresql-python:
   pkg.installed:
-    - name: {{ postgres.pkg_python}}
+    - name: {{ postgres.pkg_python }}
   {% if postgres.fromrepo %}
     - fromrepo: {{ postgres.fromrepo }}
   {% endif %}