Bump chardet from 3.0.4 to 4.0.0 (#5334)

Bumps [chardet](https://github.com/chardet/chardet) from 3.0.4 to 4.0.0.
- [Release notes](https://github.com/chardet/chardet/releases)
- [Commits](chardet/chardet@3.0.4...4.0.0)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

requirements/base.txt

@@ -8,7 +8,7 @@ asynctest==0.13.0; python_version<"3.8"
 attrs==20.3.0
 brotlipy==0.7.0
 cchardet==2.1.7
-chardet==3.0.4
+chardet==4.0.0
 frozenlist==1.1.1
 gunicorn==20.0.4
 idna-ssl==1.1.0; python_version<"3.7"

setup.py

@@ -64,7 +64,7 @@ def build_extension(self, ext):
 
 install_requires = [
     "attrs>=17.3.0",
-    "chardet>=2.0,<4.0",
+    "chardet>=2.0,<5.0",
     "multidict>=4.5,<7.0",
     "async_timeout>=4.0.0a3,<5.0",
     'asynctest==0.13.0; python_version<"3.8"',