fix(rdb): handle pointer type in instance create engine autocomplete (#4863)

Co-authored-by: protobuf-ci-cd <protobuf-ci-cd@scaleway.com>

Author: jremy42

internal/namespaces/rdb/v1/custom_instance.go

@@ -253,7 +253,15 @@ func autoCompleteDatabaseEngines(
 prefix string,
 request any,
 ) core.AutocompleteSuggestions {
-req := request.(rdbCreateInstanceRequestCustom)
+var req *rdbCreateInstanceRequestCustom
+switch v := request.(type) {
+case rdbCreateInstanceRequestCustom:
+req = &v
+case *rdbCreateInstanceRequestCustom:
+req = v
+default:
+return nil
+}
 suggestion := core.AutocompleteSuggestions(nil)
 client := core.ExtractClient(ctx)
 api := rdbSDK.NewAPI(client)