FIX a number of race conditions in threadpoolctl's OpenBLAS-pthreads ownership - #300

Internal server error. Correlation ID: dfa32cdd-2dca-4564-bba0-0160764de6cf

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@v3, actions/setup-python@v4. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/