fix(docker-image): update app-template docker tag to v3.0.4 (#391)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| app-template | patch | `3.0.3` -> `3.0.4` |

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kubernetes/main/apps/monitoring/alertmanager/app/helmrelease.yaml

@@ -9,7 +9,7 @@ spec:
   chart:
     spec:
       chart: app-template
-      version: 3.0.3
+      version: 3.0.4
       interval: 30m
       sourceRef:
         kind: HelmRepository

kubernetes/main/apps/monitoring/kromgo/app/helmrelease.yaml

@@ -9,7 +9,7 @@ spec:
   chart:
     spec:
       chart: app-template
-      version: 3.0.3
+      version: 3.0.4
       interval: 30m
       sourceRef:
         kind: HelmRepository

kubernetes/main/apps/network/cloudflared/app/helmrelease.yaml

@@ -9,7 +9,7 @@ spec:
   chart:
     spec:
       chart: app-template
-      version: 3.0.3
+      version: 3.0.4
       interval: 30m
       sourceRef:
         kind: HelmRepository

kubernetes/main/apps/network/echo-server/app/helmrelease.yaml

@@ -9,7 +9,7 @@ spec:
   chart:
     spec:
       chart: app-template
-      version: 3.0.3
+      version: 3.0.4
       interval: 30m
       sourceRef:
         kind: HelmRepository