Bump pyjwt from 1.4.0 to 2.4.0

Bumps [pyjwt](https://github.com/jpadilla/pyjwt) from 1.4.0 to 2.4.0.
- [Release notes](https://github.com/jpadilla/pyjwt/releases)
- [Changelog](https://github.com/jpadilla/pyjwt/blob/master/CHANGELOG.rst)
- [Commits](jpadilla/pyjwt@1.4.0...2.4.0)

---
updated-dependencies:
- dependency-name: pyjwt
  dependency-type: direct:production
...

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

requirements.txt

@@ -38,7 +38,7 @@ pycodestyle==2.7.0
 pycparser==2.17
 pycrypto==2.6.1
 pyflakes==2.3.0
-PyJWT==1.4.0
+PyJWT==2.4.0
 pylint==1.6.4
 pyparsing==2.2.0
 pytest==4.6.9