Attempt to solve the problem in PyPy

Author: abravalheri

pytest.ini

@@ -19,10 +19,10 @@ filterwarnings=
 	default::ResourceWarning
 
 	# python/mypy#17057
-	ignore:'encoding' argument not specified::mypy.config_parser
-	ignore:'encoding' argument not specified::mypy.build
-	ignore:'encoding' argument not specified::mypy.modulefinder
-	ignore:'encoding' argument not specified::mypy.metastore
+	ignore:'encoding' argument not specified::mypy
+	ignore:'encoding' argument not specified::configparser
+	# ^-- ConfigParser is called by mypy,
+	#     but ignoring the warning in `mypy` is not enough on PyPy
 
 	# realpython/pytest-mypy#152
 	ignore:'encoding' argument not specified::pytest_mypy