max-time.py:
Windows does not have a native `sleep` command, use `time.sleep()` in
Python instead.
max-failures.py:
The max-failure test reused the shtest-shell test inputs instead of
defining its own "test domain". However, the output of this
shtest-shell "test domain" is slightly different on Windows, which now
bites us since we made the max-failures test stricter. Let's define
our own "max failures" test domain.
Track and print the number of skipped tests. Skipped tests are tests
that should have been executed but weren't due to:
* user interrupt [Ctrl+C]
* --max-time (overall lit timeout)
* --max-failures
This is part of a larger effort to ensure that all discovered tests are
properly accounted for.
Add test for overall lit timeout feature (`--max-time` option) to
observe skipped tests. Extend test for `--max-failures` option.
Reviewed By: jdenny
Differential Revision: https://reviews.llvm.org/D77819