Reduce some file system paths' lengths

[DaniPopes]

Removes ./test/cmdlineTests/standard_model_checker_show_unsupported_false_all_engines/standard_model_checker_show_unsupported_false_all_enginesstandard_model_checker_show_unsupported_false_bmc.

Fixes #15688.

[github-actions]

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[r0qs]

Hi @DaniPopes thanks for finding this. This test was not even been run because it is indeed in the wrong subdirectory so our test suite couldn't find it. But after taking a look at the test, it does not make sense to have it, since this one here: https://github.com/ethereum/solidity/blob/develop/test/cmdlineTests/standard_model_checker_show_unsupported_false_all_engines/input.json already test the same thing.

Could you please just remove this test?

[r0qs]

Thanks. The failing CI tests are unrelated and we are taking a look at it :)