Update Django to 4.0

Author: jelly

.github/workflows/main.yml

@@ -9,10 +9,10 @@ jobs:
 
     steps:
     - uses: actions/checkout@v1
-    - name: Set up Python 3.7
+    - name: Set up Python 3.9
       uses: actions/setup-python@v1
       with:
-        python-version: 3.7
+        python-version: 3.9
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip

requirements.txt

@@ -1,5 +1,5 @@
 -e git+git://github.com/fredj/cssmin.git@master#egg=cssmin
-Django==3.2.8
+Django==4.0
 IPy==1.1
 Markdown==3.3.4
 bencode.py==4.0.0