Bump py from 1.9.0 to 1.10.0 in /tests

tests/requirements.txt

@@ -4,16 +4,27 @@
 #
 #    pip-compile --output-file=requirements.txt requirements.in
 #
-attrs==19.3.0              # via pytest
-coverage==5.2              # via pytest-cov
-importlib-metadata==1.7.0  # via pluggy, pytest
-more-itertools==8.4.0      # via pytest
-packaging==20.4            # via pytest
-pluggy==0.13.1             # via pytest
-py==1.9.0                  # via pytest
-pyparsing==2.4.7           # via packaging
-pytest-cov==2.10.0         # via -r requirements.in
-pytest==5.4.3              # via -r requirements.in, pytest-cov
-six==1.15.0                # via packaging
-wcwidth==0.2.5             # via pytest
-zipp==3.1.0                # via importlib-metadata
+attrs==19.3.0
+    # via pytest
+coverage==5.2
+    # via pytest-cov
+more-itertools==8.4.0
+    # via pytest
+packaging==20.4
+    # via pytest
+pluggy==0.13.1
+    # via pytest
+py==1.10.0
+    # via pytest
+pyparsing==2.4.7
+    # via packaging
+pytest-cov==2.10.0
+    # via -r requirements.in
+pytest==5.4.3
+    # via
+    #   -r requirements.in
+    #   pytest-cov
+six==1.15.0
+    # via packaging
+wcwidth==0.2.5
+    # via pytest