Update known-good versions of tinycss2 (#732)

Author: willkg

setup.py

@@ -32,7 +32,7 @@ def get_version():
 
 EXTRAS_REQUIRE = {
     "css": [
-        "tinycss2>=1.1.0,<1.3",
+        "tinycss2>=1.1.0,<1.5",
     ],
 }