ci: add chart testing (#111)

- closes #18

Reviewed-on: https://codeberg.org/forgejo-contrib/forgejo-helm/pulls/111
Co-authored-by: Michael Kriese <michael.kriese@visualon.de>
Co-committed-by: Michael Kriese <michael.kriese@visualon.de>

.woodpecker/e2e.yml

@@ -0,0 +1,48 @@
+platform: linux/amd64
+
+when:
+  event:
+    - pull_request
+    - push
+  branch:
+    - main
+    - release/**
+
+services:
+  docker:
+    image: docker:24.0.7-dind
+    pull: true
+    environment:
+      DOCKER_TLS_CERTDIR: ''
+
+matrix:
+  k8s:
+    # from https://hub.docker.com/r/kindest/node/tags
+    #    - v1.25.3 # renovate: kindest
+    - v1.28.0 # renovate: kindest
+
+pipeline:
+  create-cluster:
+    image: alpine:3.18.5
+    pull: true
+    environment:
+      DOCKER_HOST: tcp://docker:2375
+    commands:
+      - apk add docker-cli kind
+      - export KUBECONFIG=$${CI_WORKSPACE}/kube.config
+      - sleep 15s
+      - docker info
+      - kind create cluster --config e2e/kind.cluster.yml --image kindest/node:${k8s} --wait 1m
+      - kind get clusters
+      - docker ps
+      # replace localhost or 0.0.0.0 in the kubeconfig file with "docker", in order to be able to reach the cluster through the docker service
+      - sed -i -E -e 's/localhost|0\.0\.0\.0/docker/g' $${KUBECONFIG}
+
+  chart-testing:
+    image: quay.io/helmpack/chart-testing:v3.10.1
+    pull: true
+    commands:
+      - git fetch --no-tags --filter=blob:none origin
+      - export KUBECONFIG=$${CI_WORKSPACE}/kube.config
+      - kubectl get no -o wide
+      - ct install --config tools/ct.yml --charts .