This field was deprecated in 0c182d4d57,
which should be included in a 28.x release, but we don't need to carry
it in the new module.
We should also considering duplicating the `ExecOptions` type as a client
option, and renaming it to `ExecCreateRequest`, so that we can decouple
client options from the shape of the request.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
caae209d25