feat: Support HelmReleases

[laszlocph]

• FluxState should get a new field HelmReleases https://github.com/gimlet-io/capacitor/blob/main/pkg/flux/types.go#L10
• SideBar should get an new nav item: Helm Releases as the second option, right after Kustomizations https://github.com/gimlet-io/capacitor/blob/main/web/src/Footer.js#L39
  • Navigating to Helm Releases should display Helm Releases like we display Kustomizations
• /api/services endpoint should return services that are created by Helm
  • How to get Kubernetes resources deployed by Helm is implemented in Helm and best visible in the helm status $RELEASE_NAME --show-resources command. The source code of the command shows how it is done: https://github.com/helm/helm/blob/main/pkg/action/status.go#L58.