Remove faststartup from the test matrix
Remove faststartup from the test matrix

Context: we finally removed the old emitter and fast startup is on by default.
This CL removes from the test matrix duplicate steps that now are doing the same
thing and the faststartup builders that are no longer needed.

Change-Id: Id65ea3178bcd7a9554bfa127a09938ca910c57e8
Reviewed-on: https://dart-review.googlesource.com/c/89181
Reviewed-by: Sigmund Cherem <beaea8fd7d2a56555046ba4f362c8a93e3938576@google.com>
Reviewed-by: Alexander Thomas <29642742b6693024c89de8232f2e2542cf7eedf7@google.com>
Reviewed-by: William Hesse <a821cddceae7dc400f272e3cb1a72f400f9fed6d@google.com>
Commit-Queue: Sigmund Cherem <beaea8fd7d2a56555046ba4f362c8a93e3938576@google.com>

dartino/dart-sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dartino/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dartino/dart-sdk,dartino/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk,dartino/dart-sdk,dart-lang/sdk,dartino/dart-sdk,dart-archive/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk