feat: Use list of dict for environment

templates/podman-quadlet.container.j2

@@ -39,7 +39,7 @@ PublishPort={{ port }}
 {% endfor %}
 
 {% for environment in container.get('environment_vars', []) %}
-Environment={{ environment }}
+Environment={{ environment.keys() | first }}={{ environment.values() | first }}
 {% endfor %}
 
 [Service]