AuthN: Add IsAuthenticatedBy to identity interface and replace checks (#85262)

Add IsAuthenticatedBy to identity interface and replace checks

pkg/services/user/identity.go

@@ -217,6 +217,15 @@ func (u *SignedInUser) GetNamespacedID() (string, string) {
 	return parts[0], parts[1]
 }
 
+func (u *SignedInUser) IsAuthenticatedBy(providers ...string) bool {
+	for _, p := range providers {
+		if u.AuthenticatedBy == p {
+			return true
+		}
+	}
+	return false
+}
+
 // FIXME: remove this method once all services are using an interface
 func (u *SignedInUser) IsNil() bool {
 	return u == nil