change async to non_blocking

6 jobs for fix_py37_compatibility in 30 minutes and 18 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Build
passed #173629
docker
build_linux_36

00:27:34

72.0%
passed #173630
docker
build_linux_37

00:26:10

72.0%
passed #173639
macosx
build_macosx_36

00:02:40

passed #173628
macosx
build_macosx_37

00:01:49

failed #173631
macosx
build_macosx_36

00:00

failed #173627
macosx
build_macosx_36

00:00:01