refactor(all): move e2e tests to example/test_driver and update docs

[miquelbeltran]

Description

Moved all e2e tests to the example/test_driver folder.

Related Issues

• [all] e2e test folder location #28

Breaking Change

Does your PR require plugin users to manually update their apps to accommodate your change?

• No, this is not a breaking change.

[jpnurmi]

• Move sensors_plus/test/sensors_e2e.dart to sensors_plus/example/test_driver/, and
• remove connectivity_plus/test/connectivity_e2e.dart (looks like duplicate of the one in test_driver)?

P.S. Are these missing how does one run flutter drive for battery & share?

• battery_plus/example/test_driver/battery_e2e_test.dart
• share_plus/example/test_driver/share_e2e.dart

[miquelbeltran]

Thanks for checking those!

• sensors -> fixed
• connectivity -> removed duplicated
• share -> looks like the original share_test.dart was the e2e, so renamed and moved.
• battery -> looks like the battery_e2e_test.dart was originally missing

[miquelbeltran]

I added the missing batter_e2e_test.dart and I was able to run and pass the test with flutter drive --target=./test_driver/battery_e2e.dart

[jpnurmi]

Awesome!