K8s/Folders: Fix folder status error message (#95464)

* Fix folder status error message
* Add test for folder creation response message
* Add TestFoldersCreateAPIEndpointK8S fixes
* Fix message returned when user has no permissions

pkg/api/apierrors/folder.go

@@ -1,6 +1,7 @@
 package apierrors
 
 import (
+	"encoding/json"
 	"errors"
 	"net/http"
 
@@ -48,20 +49,36 @@ func ToFolderErrorResponse(err error) response.Response {
 
 func ToFolderStatusError(err error) k8sErrors.StatusError {
 	resp := ToFolderErrorResponse(err)
+	defaultErr := k8sErrors.StatusError{
+		ErrStatus: metav1.Status{
+			Message: "Folder API error",
+			Code:    http.StatusInternalServerError,
+		},
+	}
 
 	normResp, ok := resp.(*response.NormalResponse)
 	if !ok {
-		return k8sErrors.StatusError{
-			ErrStatus: metav1.Status{
-				Message: "Folder API error",
-				Code:    http.StatusInternalServerError,
-			},
-		}
+		return defaultErr
+	}
+
+	var dat map[string]interface{}
+	if err := json.Unmarshal(normResp.Body(), &dat); err != nil {
+		return defaultErr
+	}
+
+	m, ok := dat["message"]
+	if !ok {
+		return defaultErr
+	}
+
+	message, ok := m.(string)
+	if !ok {
+		return defaultErr
 	}
 
 	return k8sErrors.StatusError{
 		ErrStatus: metav1.Status{
-			Message: normResp.ErrMessage(),
+			Message: message,
 			Code:    int32(normResp.Status()),
 		},
 	}