Relay: improve types of 'handleData'

This change improves some internal types in Relay reported by Jakub Ž. Internal type of `response.json()` is `Promise<any>` so I just removed the type completely. This change doesn't affect anyone since it's internal only.

Closes: https://gitlab.skypicker.com/incubator/universe/issues/458

package.json

@@ -2,7 +2,7 @@
   "name": "@kiwicom/fetch",
   "private": false,
   "license": "MIT",
-  "version": "2.2.2",
+  "version": "2.2.3",
   "main": "src/fetchWithRetries.js",
   "homepage": "https://github.com/kiwicom/fetch",
   "description": "Production ready fetch function with advanced capabilities like retries with delay and request cancellation after timeout.",

src/ResponseError.js

@@ -1,11 +1,11 @@
-// @flow
+// @flow strict-local
 
 import setPrototypeOf from './setPrototypeOf';
 
 /**
  * @see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error#Custom_Error_Types
  */
-function ResponseError(response: Object, message?: string) {
+function ResponseError(response: Response, message?: string) {
   // property 'error.response' is unknown in Error (but that's fine, we are extending here)
   // $FlowExpectedError: ^^
   const instance = new Error(message);

src/TimeoutError.js

@@ -1,4 +1,4 @@
-// @flow
+// @flow strict-local
 
 import setPrototypeOf from './setPrototypeOf';
 

src/__tests__/ResponseError.test.js

@@ -2,6 +2,7 @@
 
 import { ResponseError } from '../fetchWithRetries';
 
+// $FlowExpectedError: incomplete Response object for testing purposes only
 const fetchResponse = {
   status: 403,
 };

src/fetchWithRetries.js

@@ -1,4 +1,4 @@
-// @flow
+// @flow strict-local
 
 import { sprintf, warning } from '@kiwicom/js';
 
@@ -24,7 +24,7 @@ export { TimeoutError, ResponseError };
 export default function fetchWithRetries(
   uri: string,
   initWithRetries?: ?InitWithRetries,
-): Promise<any> {
+): Promise<Response> {
   const { fetchTimeout, retryDelays, ...init } = initWithRetries || {};
   const _fetchTimeout = fetchTimeout != null ? fetchTimeout : DEFAULT_TIMEOUT;
   const _retryDelays = retryDelays != null ? retryDelays : DEFAULT_RETRIES;