build: ensure numpy available

.github/workflows/test.yml

@@ -28,7 +28,7 @@ jobs:
           BUILD_WITH_CYTHON: 1 # for pysimdjson
       run: |
         python -m pip install --upgrade pip
-        pip install -r requirements.txt pytest cython
+        pip install -r requirements.txt pytest cython numpy
         pip install -e .
     - name: Test with pytest
       run: |