Set UNSAFE_PYO3_SKIP_VERSION_CHECK=1 for Python 3.13. (#58)

Co-authored-by: repo-helper[bot] <74742576+repo-helper[bot]@users.noreply.github.com>

Author: repo-helper[bot]

tox.ini

@@ -66,6 +66,7 @@ setenv =
  PYTHONDEVMODE=1
  PIP_DISABLE_PIP_VERSION_CHECK=1
  PIP_PREFER_BINARY=1
+ UNSAFE_PYO3_SKIP_VERSION_CHECK=1
 skip_install = True
 changedir = {toxinidir}
 deps =