py-test: updated to 3.10.1

pytest 3.10.1:

Bug Fixes
- Fix nested usage of debugging plugin (pdb), e.g. with pytester's testdir.runpytest.
- Block the stepwise plugin if cacheprovider is also blocked, as one depends on the other.
- Parse minversion as an actual version and not as dot-separated strings.
- Fix duplicate collection due to multiple args matching the same packages.
- Fix item.nodeid with resolved symlinks.
- Fix collection of direct symlinked files, where the target does not match python_files.
- Fix TypeError in report_collect with _collect_report_last_write.

Trivial/Internal Changes
- Replace byte/unicode helpers in test_capture with python level syntax.

(adam)