Use np directly, install numpy in GHA

Author: jamescooke

.github/workflows/ci.yaml

@@ -16,6 +16,7 @@ jobs:
       - name: Install dependencies
         run: |
           python setup.py develop
+          pip install numpy
 
       - name: Test
         shell: 'script -q -e -c "bash {0}"'

tests/test_pytest_icdiff.py

@@ -296,14 +296,13 @@ def test_one():
 
 def test_np_arrays_can_use_equals(testdir) -> None:
     """
-    NP iterables will fall back to pytest default output
+    Numpy iterables will fall back to pytest default output
     """
-    testdir.copy_example('tests/fakes.py')
     testdir.makepyfile("""
-    from fakes import FakeNumpyArray
+    import numpy as np
 
     def test():
-        result = FakeNumpyArray([1, 2, 3])
+        result = np.array([1, 2, 3])
 
         assert all(result == 2)
     """)