fix: remove helm from deploy-rules pipeline

.gitea/workflows/deploy-rules.yml

@@ -0,0 +1,33 @@
+name: Deploy alert rules
+
+on:
+  push:
+    branches: [main]
+    paths:
+      - 'rules/**'
+
+jobs:
+  deploy:
+    runs-on: alpine
+    steps:
+      - name: Install tools
+        run: |
+          apk add --no-cache curl bash git openssh-client openssl nodejs
+          curl -LO "https://dl.k8s.io/release/$(curl -Ls https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl"
+          chmod +x kubectl && mv kubectl /usr/local/bin/
+
+      - uses: actions/checkout@v4
+
+      - name: Configure kubeconfig
+        run: |
+          mkdir -p $HOME/.kube
+          echo "${{ secrets.KUBECONFIG }}" | base64 -d > $HOME/.kube/config
+          chmod 600 $HOME/.kube/config
+
+      - name: Deploy rules
+        run: kubectl apply -f rules/ -n monitoring
+
+      - name: Verify
+        run: |
+          sleep 10
+          kubectl get prometheusrule -n monitoring