tests/sitecustomize.py

rust: upgrade minimum `rayon` dependency

The 1.6.0 and 1.6.1 releases fixes a soundness issue and a performance issue
that are both important to us, since both correctness and performance are
paramount in the Rust extensions.

import os

if os.environ.get('COVERAGE_PROCESS_START'):
    try:
        import coverage
        import uuid

        covpath = os.path.join(
            os.environ['COVERAGE_DIR'], 'cov.%s' % uuid.uuid1()
        )
        cov = coverage.coverage(data_file=covpath, auto_data=True)
        cov._warn_no_data = False
        cov._warn_unimported_source = False
        cov.start()
    except ImportError:
        pass