Bump django from 1.11.29 to 2.2.24

Bumps [django](https://github.com/django/django) from 1.11.29 to 2.2.24.
- [Release notes](https://github.com/django/django/releases)
- [Commits](django/django@1.11.29...2.2.24)

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

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

Author: dependabot[bot]

requirements.txt

@@ -1,6 +1,6 @@
 psycopg2==2.8.6
 reportlab==3.5.55
-Django==1.11.29
+Django==2.2.24
 #ipython==7.19.0
 jedi==0.17.2
 git+https://github.com/dbca-wa/ledger#egg=ledger