[vm] Update comment for Dart_IsolateGroupCreateCallback
[vm] Update comment for Dart_IsolateGroupCreateCallback

Closes https://github.com/dart-lang/sdk/pull/41945
https://github.com/dart-lang/sdk/pull/41945

GitOrigin-RevId: 2e146cfd56cff8035cd15225902d5dd4d8eb450a
Change-Id: I2b06125be11774da2aabbc5cc7031dd91d1e1ea4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/148462
Reviewed-by: Vyacheslav Egorov <72c81f38df725d8f1832acb9b5bb99563fc2f1b9@google.com>

dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk