Update code_transformers and use transformer_test for tests

[jakemac53]

The test helpers were split out from code_transformers into their own package. For the most part this just means changing any imports to package:code_transformers/tests.dart to package:transformer_test/utils.dart.

The only actual breaking change should be that the optional args to testPhases were changed to named args.

[jakemac53]

I am looking into just sending a pr for this, if the dev environment is reasonable to set up ;)

[lassedamgaard]

Would be awesome to get this fixed as it prevents projects with a dependency on both test and angular from upgrading to dart 1.16 .

[jakemac53]

I should have updated here, but last I checked working on this repo wasn't possible because I could not pub get due to version issues... not sure if somebody else can fix this or chime in with instructions on how to get things working.

[lassedamgaard]

dart-archive/di.dart#232 needs to be fixed first