exclude numpy 1.17 on Pyhton 3.9

Author: ocefpaf

.github/workflows/tests.yml

@@ -9,17 +9,16 @@ jobs:
   run:
     runs-on: ${{ matrix.os }}
     strategy:
-      fail-fast: false
       matrix:
+        python-version: ["3.7", "3.8", "3.9"]
         os: [windows-latest, ubuntu-latest, macos-latest]
-        python-version: ["3.7", "3.8"]
         # Oldest one based on NEP-29 and latest one.
         # See https://numpy.org/neps/nep-0029-deprecation_policy.html
         numpy-version: ["1.17", "1.20"]
-        include:
+        exclude:
           - python-version: "3.9"
-            numpy-version: "1.20"
-  
+            numpy-version: "1.17"
+
     steps:
     - uses: actions/checkout@v2