chore: exclude incompatible coverage versions (#337)

Author: cdce8p

setup.py

@@ -34,7 +34,7 @@
     },
     python_requires='>= 3.5',
     install_requires=[
-        'coverage>=4.1,<7.0',
+        'coverage>=4.1,<7.0,!=6.0.*,!=6.1,!=6.1.1',
         'docopt>=0.6.1',
         'requests>=1.0.0',
     ],