fix(ci): replace volkerraschek/helm with native GitHub Actions

.gitea/workflows/helm.yaml

@@ -12,29 +12,22 @@ on:
 
 jobs:
   helm-lint:
-    container:
-      image: docker.io/volkerraschek/helm:3.19.2
     runs-on: ubuntu-latest
     steps:
-    - name: Install tooling
-      run: |
-        apk update
-        apk add git npm
     - uses: actions/checkout@v5.0.1
+    - uses: azure/setup-helm@v4.3.0
+      with:
+        version: v4.0.0 # renovate: datasource=github-releases depName=helm/helm
     - name: Lint helm files
       run: |
         helm lint --values values.yaml .
 
   helm-unittest:
-    container:
-      image: docker.io/volkerraschek/helm:3.19.2
     runs-on: ubuntu-latest
     steps:
-    - name: Install tooling
-      run: |
-        apk update
-        apk add git npm
     - uses: actions/checkout@v5.0.1
-    - name: Unittest
-      run: |
-        helm unittest --strict --file 'unittests/**/*.yaml' ./
+    - uses: d3adb5/helm-unittest-action@v2.5.0
+      with:
+        flags: --color --strict --file 'unittests/**/*.yaml'
+        helm-version: v4.0.0 # renovate: datasource=github-releases depName=helm/helm
+        unittest-version: v1.0.0 #renovate: datasource=github-releases depName=helm-unittest/helm-unittest