Podman: Correct Quadlet install mechanism (#2294)

Quadlet services do not support enabling by `systemd enable`.
Remove the wrong section and replace it with hint about the generator
procedure.

docs/gemstones/containers/podman.md

@@ -86,12 +86,7 @@ To automatically run the container upon system start or user login, you can add
 WantedBy=default.target
 ```
 
-Then let the generator run again and enable your service:
-
-```bash
-systemctl --user daemon-reload;
-systemctl --user enable nextcloud.service;
-```
+As the generated service files are considered transient, they cannot be enabled by systemd. To mitigate this, the generator manually applies installs during generation. This effectively also enables those services files.
 
 Other file types are supported: pod, volume, network, image, and kube. [Pods](https://docs.podman.io/en/latest/markdown/podman-systemd.unit.5.html#pod-units-pod), for instance, can be used to group containers – the generated systemd services and their dependencies (create the pod before the containers) are automatically managed by systemd.
 

docs/guides/containers/podman_guide.md

@@ -163,12 +163,7 @@ To automatically run the container upon system start or user login, you can add
 WantedBy=default.target
 ```
 
-Then let the generator run again and enable your service:
-
-```bash
-systemctl --user daemon-reload;
-systemctl --user enable nextcloud.service;
-```
+As the generated service files are considered transient, they cannot be enabled by systemd. To mitigate this, the generator manually applies installs during generation. This effectively also enables those services files.
 
 Other file types are supported: pod, volume, network, image, and kube. [Pods](https://docs.podman.io/en/latest/markdown/podman-systemd.unit.5.html#pod-units-pod), for instance, can be used to group containers – the generated systemd services and their dependencies (create the pod before the containers) are automatically managed by systemd.