CB-12439 (Tests) Re-enable the tests
CB-12439 (Tests) Re-enable the tests

* This is a part of file transfer CI builds being transferred to Sauce Labs emulators
* Some tests now retry up to 100 times due to Heroku server being unstable
* Now using '/upload_headers_echo' of the FT server instead of whatheaders.com which is down

starquake/cordova-plugin-file-transfer,apache/cordova-plugin-file-transfer,purplecabbage/cordova-plugin-file-transfer,alsorokin/cordova-plugin-file-transfer,starquake/cordova-plugin-file-transfer,alsorokin/cordova-plugin-file-transfer,bcalvez/cordova-plugin-file-transfer,starquake/cordova-plugin-file-transfer,starquake/cordova-plugin-file-transfer,purplecabbage/cordova-plugin-file-transfer,purplecabbage/cordova-plugin-file-transfer,alsorokin/cordova-plugin-file-transfer,apache/cordova-plugin-file-transfer,bcalvez/cordova-plugin-file-transfer,purplecabbage/cordova-plugin-file-transfer,alsorokin/cordova-plugin-file-transfer