Merge branch 'renovate/alpine-helm-3.x' into 'master'

Update alpine/helm Docker tag to v3.13.0

See merge request !33

.gitlab-ci.yml

@@ -16,7 +16,7 @@ stages:
 lint:
   stage: test
   image:
-    name: alpine/helm:3.12.3
+    name: alpine/helm:3.13.0
     entrypoint: ["/bin/sh", "-c"]
   script:
     - helm lint $CHART
@@ -29,7 +29,7 @@ lint:
 package_charts:
   stage: package
   image:
-    name: alpine/helm:3.12.3
+    name: alpine/helm:3.13.0
     entrypoint: ["/bin/sh", "-c"]
   script:
     # The helm-push command is broken in Helm 3.7. For more information,