docs: public ApiResponse<RefreshTokenResponse> refreshTokenWithHttpInfo(String grantType, String refreshToken) throws ApiException {
          com.squareup.okhttp.Call call = refreshTokenValidateBeforeCall(grantType, refreshToken, null, null);
          Type localVarReturnType = new TypeToken<RefreshTokenResponse>(){}.getType();
          return apiClient.execute(call, localVarReturnType);
      }