run-tests: ensure that --no-rust do not use rust Since having a valid value in HGWITHRUSTEXT is enough to trigger the use of rust, we need to unset it before install to be sure.

rust: bump rust-cpython version to 0.7.2 This version supports Python 3.12 while 0.7.1 did not.

profiling: use "stat" profiler to profile individual request The ls profiler no longer works for that. As the lsprof profiler is not default and not great is general, lets side step the issue for now.