less xOS

.github/workflows/ci-testing.yml

@@ -13,6 +13,9 @@ jobs:
         os: [ubuntu-18.04, macOS-10.15]  #, windows-2019
         python-version: [3.7, 3.8]
         yolo5-model: ["yolov5s", "yolov5m", "yolov5l", "yolov5x"]
+        exclude:
+          - python-version: 3.8
+            os: macOS-10.15
 
     # Timeout: https://stackoverflow.com/a/59076067/4521646
     timeout-minutes: 50