fix(deps): update module helm.sh/helm/v3 to v4

Author: elastic-renovate-prod[bot]

hack/helm/release/go.mod

@@ -10,7 +10,7 @@ require (
 	github.com/spf13/viper v1.21.0
 	google.golang.org/api v0.255.0
 	gopkg.in/yaml.v3 v3.0.1
-	helm.sh/helm/v3 v3.19.1
+	helm.sh/helm/v3/v4 v4.0.0
 )
 
 replace github.com/elastic/cloud-on-k8s/v3 => ../../..

hack/manifest-gen/go.mod

@@ -6,7 +6,7 @@ toolchain go1.25.4
 
 require (
 	github.com/spf13/cobra v1.10.1
-	helm.sh/helm/v3 v3.19.1
+	helm.sh/helm/v3/v4 v4.0.0
 	sigs.k8s.io/kustomize/kyaml v0.21.0
 )