build(deps): bump chardet from 3.0.4 to 4.0.0

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-preview[bot] <support@dependabot.com>

Author: dependabot-preview[bot]

requirements-pinned.txt

@@ -1,6 +1,6 @@
 certifi==2020.12.5        # via requests
 cffi==1.14.4              # via cryptography, pynacl
-chardet==3.0.4            # via requests
+chardet==4.0.0            # via requests
 cryptography==3.3.1       # via securesystemslib
 enum34==1.1.10            ; python_version < '3' # via cryptography
 idna==2.10                # via requests