[gardening] mark sample_extension_test as error
[gardening] mark sample_extension_test as error

sample_extension/test/sample_extension_test is still a RuntimeError on
dartk for now (see commentary on #33711).

Change-Id: I55ec54fa8c8ff2ebb42409a38cc216a2e7faeb2a
Reviewed-on: https://dart-review.googlesource.com/c/86763
Commit-Queue: Stevie Strickland <cce218d042444252b7ac446d60910fca7732559c@google.com>
Reviewed-by: Stevie Strickland <cce218d042444252b7ac446d60910fca7732559c@google.com>
Auto-Submit: Stevie Strickland <cce218d042444252b7ac446d60910fca7732559c@google.com>

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