Fixed a deadlock when gdal.Warp was called by a multiprocessing child process...

Fixed a deadlock when gdal.Warp was called by a  multiprocessing child process and GDAL_NUM_THREADS was set (only GDAL 3.2.1 and above).

Signed-off-by: Daniel Scheffler <danschef@gfz-potsdam.de>
4 jobs for v0.17.2 in 2 minutes and 30 seconds (queued for 11 minutes and 27 seconds)
latest
Status Name Job ID Coverage
  Test
passed test_py_tools_ds #80138

00:00:39

69.0%
passed test_styles #80139

00:00:26

passed test_urls #80140

00:00:49

 
  Deploy Pypi
passed deploy_pypi #80141

00:00:34