[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/support/MockPushAdapter.js

@@ -0,0 +1,9 @@
+module.exports = function (options) {
+  return {
+    options: options,
+    send: function () {},
+    getValidPushTypes: function () {
+      return Object.keys(options.options);
+    },
+  };
+};