Bump jsmin dependency to 3.0.0 to work around use_2to3 issue. (#757)

Author: jezdez

tox.ini

@@ -37,7 +37,7 @@ deps =
   djmain: https://github.com/django/django/archive/main.tar.gz
   jinja2
   coverage
-  jsmin==2.2.0
+  jsmin==3.0.0
   ply==3.4
   slimit==0.8.1
   css-html-js-minify==2.5.5