cmd/cue: remove test files related to old old closedness

These two test files related to a closedness implementation from 2020.
It is not clear from the test files or the associated CLs:

    https://cue-review.googlesource.com/c/cue/+/7002
    https://cue-review.googlesource.com/c/cue/+/7142

what precisely was being exercised.

In an upcoming CL we make it an error for a command to do nothing. As
such, we cannot be clear that fixing the commands in each to actually
run a task doesn't invalidate the setup that caused the test case to be
created in the first place.

We instead prefer to remove these test files and rely on evaluator
coverage to ensure we do not regress in the current evaluation
(evalv3=1).

Signed-off-by: Paul Jolly <[email protected]>
Change-Id: Ib44bd9a71b3ac789f2010e7c196bac7bb1520f65
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1213881
TryBot-Result: CUEcueckoo <[email protected]>
Reviewed-by: Roger Peppe <[email protected]>
Unity-Result: CUE porcuepine <[email protected]>

Author: myitcv