Update test expectations for multiline_strings_test on windows [TBR].
Update test expectations for multiline_strings_test on windows [TBR].

See: https://github.com/dart-lang/sdk/issues/30336

.gitattributes updated.

Bug:
Change-Id: I7481362e64159ba28b8448d19acca5817010739d
Reviewed-on: https://dart-review.googlesource.com/7383
Reviewed-by: Phil Quitslund <3faecbdd7b7be83f493f037bf1d597e6bb9d0848@google.com>

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