[WIP] Enable test suite to be randomized (#7265)

* initial run

* Update ParseGraphQLServer.spec.js

* temporarily enable reporter

* Bump retry limit

* fix undefined database

* try to catch error

* Handle LiveQueryServers

* Update Config.js

* fast-fail false

* Remove usage of AppCache

* oops

* Update contributing guide

* enable debugger, try network retry attempt 1

* Fix ldap unbinding

* move non specs to support

* add missing mock adapter

* fix Parse.Push

* RestController should match batch.spec.js

* Remove request attempt limit

* handle index.spec.js

* Update CHANGELOG.md

* Handle error: tuple concurrently updated

* test transactions

* Clear RedisCache after every test

* LoggerController.spec.js

* Update schemas.spec.js

* finally fix transactions

* fix geopoint deadlock

* transaction with clean database

* batch.spec.js

spec/FilesController.spec.js

@@ -80,6 +80,9 @@ describe('FilesController', () => {
     expect(typeof error).toBe('object');
     expect(error.message.indexOf('biscuit')).toBe(13);
     expect(error.code).toBe(Parse.Error.INVALID_FILE_NAME);
+    mockAdapter.validateFilename = () => {
+      return null;
+    };
     done();
   });