Add a "Setup Python" action for github-hosted runners and remove unnecessary CUSTOM_MINGW environment variable
#125083
| Job | Run time |
|---|---|
| 10s | |
| 26m 35s | |
| 5m 19s | |
| 52m 56s | |
| 44m 45s | |
| 0s | |
| 2h 9m 45s |