Update test requirements

Author: hackermd

requirements_test.txt

@@ -1,7 +1,7 @@
-mypy==0.941
-pytest==6.2.4
-pytest-cov==2.12.1
-pytest-flake8==1.0.7
+mypy==0.960
+pytest==7.1.2
+pytest-cov==3.0.0
+pytest-flake8==1.1.1
 pytest-localserver==0.5.0
 types-requests==2.27.14
 types-Pillow==9.0.8