Update ghcr.io/wg-easy/wg-easy Docker tag to v15.5.0 (#36)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/wg-easy/wg-easy | minor | `15.4.0` → `15.5.0` |

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Reviewed-on: #36

apps/infra/wg-easy.yaml

@@ -43,7 +43,7 @@ spec:
               weight: 100
       containers:
         - name: wg-easy
-          image: ghcr.io/wg-easy/wg-easy:15.4.0
+          image: ghcr.io/wg-easy/wg-easy:15.5.0
           ports:
             - containerPort: 51820
               protocol: UDP