test: regression with --force and cram tests

[Alizter]

Previously, --force would re-run already run cram tests. However this is no longer the case.

Here is the test with 3.19 before #11994:

 |side-effect should only contain a single "run":
 |
 |  $ cat side-effect
 |  run
+|  run
 |
 |However, if passing --force, we should still be able to re-run cram tests:
 |
 |  $ dune runtest foo.t --force
 |
 |There should be two "run"s here, however there is only one:
 |  $ cat side-effect
 |  run
+|  run
+|  run

[rgrinberg]

Thanks for catching this. For now, let's just note this in the changes. Using --force is only useful for broken cram tests anyway, and the issue is easily worked around by inserting a dummy edit into the test.

[Alizter]

For now, I've been doing dune clean and dune build --cache disabled when I need to rerun cram tests. Typically its due to missing dependencies that I get a cache hit on a test that no longer runs correctly.

[Alizter]

If --force is only useful for cram tests and it no longer works there, shouldn't we remove it, or at least throw a warning when people use it?

[rgrinberg]

We removed it internally because it was of little use. Not sure what we're going to do about it, but I wouldn't worry about it's fate very much.