Update netbird to v0.73.2 (#8)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| netbirdio/netbird | minor | `0.72.4-rootless` → `v0.73.2-rootless` |
| netbirdio/netbird-server | minor | `0.72.4` → `0.73.2` |
| netbirdio/reverse-proxy | minor | `0.72.4` → `0.73.2` |

---

> ⚠️ **Warning**
>
> Some dependencies could not be looked up. Check the warning logs for more information.

---

### Configuration

📅 **Schedule**: (UTC)

- Branch creation
  - At any time (no schedule defined)
- Automerge
  - At any time (no schedule defined)

🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied.

♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about these updates again.

---

 - [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check this box

---

This PR has been generated by [Mend Renovate](https://github.com/renovatebot/renovate).
<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiI0My4xNTAuMSIsInVwZGF0ZWRJblZlciI6IjQzLjE1MC4xIiwidGFyZ2V0QnJhbmNoIjoibWFpbiIsImxhYmVscyI6W119-->

Reviewed-on: #8
Co-authored-by: Renovate Bot <renovate@jfreudenberger.de>
Co-committed-by: Renovate Bot <renovate@jfreudenberger.de>

modules/netbird-client.nix

@@ -62,7 +62,7 @@ in {
 
     virtualisation.oci-containers.containers = lib.mkIf (cfg.docker.setupKey != null) {
       netbird = {
-        image = "netbirdio/netbird:0.72.4-rootless@sha256:d42136aabccb82c5237d2ee73febde237e13e850727bcb6bbf5b3c8717ece142";
+        image = "netbirdio/netbird:v0.73.2-rootless@sha256:4f1893ea708f7f0cdafc6f77f400415e2a81350db57f0fa74dda3c2d6bd02772";
         autoStart = true;
         hostname = "${config.networking.hostName}-docker";
         networks = [