Refactor Helm deployments (#341)

* Wrap KMS deployment in one main chart that
deploys all other services. Other services will follow.
* Use .tgz via helm-package as serialization format
* Change Release type to carry chart as byte slice
* Remove KMSConfig
* Use json-schema to validate values
* Extend release.md to mention updating helm charts

internal/deploy/helm/helm.go

@@ -6,17 +6,15 @@ SPDX-License-Identifier: AGPL-3.0-only
 
 package helm
 
-import "helm.sh/helm/v3/pkg/chart"
-
 // Release bundles all information necessary to create a helm release.
 type Release struct {
-	Chart       *chart.Chart
+	Chart       []byte
 	Values      map[string]interface{}
 	ReleaseName string
 	Wait        bool
 }
 
 type Releases struct {
-	Cilium Release
-	KMS    Release
+	Cilium                Release
+	ConstellationServices Release
 }