Lock "click" dependency for Python 3.6

setup.py

@@ -29,7 +29,7 @@ from platformio.compat import PY2
 
 minimal_requirements = [
     "bottle==0.12.*",
-    "click>=8.0.3,<9",
+    "click%s" % (">=8.0.3,<9" if sys.version_info >= (3, 7) else "==8.0.4"),
     "colorama",
     "marshmallow%s" % (">=2,<3" if PY2 else ">=2,<4"),
     "pyelftools>=0.27,<1",