Fix: update go.mod following recent review commits

Author: mrajagopal

go.mod

@@ -5,6 +5,7 @@ go 1.24.3
 require (
 	github.com/mittwald/go-helm-client v0.12.18
 	github.com/spf13/cobra v1.10.1
+	github.com/stretchr/testify v1.10.0
 	go.uber.org/mock v0.5.0
 	helm.sh/helm/v3 v3.18.5
 	k8s.io/client-go v0.34.0
@@ -137,5 +138,5 @@ require (
 	k8s.io/metrics v0.33.3
 	k8s.io/utils v0.0.0-20250604170112-4c0f3b243397 // indirect
 	sigs.k8s.io/json v0.0.0-20241014173422-cfa47c3a1cc8 // indirect
-	sigs.k8s.io/yaml v1.6.0 // indirect
+	sigs.k8s.io/yaml v1.6.0
 )