public static String variablesToGetParamValue(final String variables) {
        return StringUtils.trimToNull(variables);
    }
@Test
    void testVariablesToGetParamValue() throws Exception {
        assertEquals(OBJECT_MAPPER.readTree(EXPECTED_VARIABLES_GET_PARAM_VALUE),
                OBJECT_MAPPER.readTree(GraphQLRequestParamUtils.variablesToGetParamValue(params.getVariables())));
    }