feat(helm): add helm chart

helm/README.md.tpl

@@ -0,0 +1,36 @@
+
+## Upgrade
+
+None
+
+
+## Develop
+
+### Update documentation
+
+Chart documentation is generated with [helm-docs](https://github.com/norwoodj/helm-docs) from `values.yaml` file.
+After file modification, regenerate README.md with command:
+
+```bash
+docker run --rm -it -v $(pwd):/helm --workdir /helm norwoodj/helm-docs helm-docs
+```
+
+### Run linter
+
+```bash
+docker run --rm -it -w /charts -v $(pwd)/../{{ .Name }}:/charts quay.io/helmpack/chart-testing:v2.4.0 ct lint --charts . --config /charts/ct.yaml
+```
+
+### Prometheus Rules
+
+Check rules:
+
+```bash
+docker run --rm --entrypoint /bin/sh -v $(pwd):/workdir -w /workdir prom/prometheus -c -- "promtool check rules resources/prometheus-rules/*"
+```
+
+Test rules:
+
+```bash
+docker run --rm --entrypoint /bin/sh -v $(pwd):/workdir -w /workdir prom/prometheus -c -- "promtool test rules tests/prometheus/*"
+```