[vendor] pin k8s.io/kube-openapi to d90c4fd18f59

Explicitly pin k8s.io/kube-openapi to a commit prior
to the structured-merge-diff v6 migration, ensuring
only v4 appears in the graph to remove the v4/v6 type
collision inside k8s.io/apimachinery managed fields code.

Author: jrvaldes

go.mod

@@ -8,6 +8,9 @@ replace (
 	// fix CVE-2025-30204 transitive deps still using older v4. Remove once `go mod graph` shows only 4.5.2 or higher
 	github.com/golang-jwt/jwt/v4 => github.com/golang-jwt/jwt/v4 v4.5.2
 	github.com/golang-jwt/jwt/v5 => github.com/golang-jwt/jwt/v5 v5.2.2
+
+	// pin kube-openapi to pre structured-merge-diff/v6 to resolve apimachinery type mismatch
+	k8s.io/kube-openapi => k8s.io/kube-openapi v0.0.0-20250628140032-d90c4fd18f59
 )
 
 require (
@@ -157,5 +160,4 @@ require (
 	sigs.k8s.io/kustomize/kyaml v0.18.1 // indirect
 	sigs.k8s.io/randfill v1.0.0 // indirect
 	sigs.k8s.io/structured-merge-diff/v4 v4.6.0 // indirect
-	sigs.k8s.io/structured-merge-diff/v6 v6.2.0 // indirect
 )