Update classifiers

Author: gasman

CHANGELOG.txt

@@ -2,7 +2,7 @@
 ------------------
 
 * Fixes for Django 4.x (Adrien Lemaire)
-* Fixes for Wagtail 4.x (Matt Westcott, Dan Braghis, Sage Abdullah)
+* Fixes for Wagtail 3.x and 4.x (Matt Westcott, Dan Braghis, Sage Abdullah)
 
 
 0.3 (2021-03-01)

setup.py

@@ -30,8 +30,11 @@
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8',
         'Programming Language :: Python :: 3.9',
+        'Programming Language :: Python :: 3.10',
         'Framework :: Django',
         'Framework :: Wagtail',
         'Framework :: Wagtail :: 2',
+        'Framework :: Wagtail :: 3',
+        'Framework :: Wagtail :: 4',
     ],
 )