build(deps): bump reportlab from 3.6.10 to 4.0.4

Bumps [reportlab](http://www.reportlab.com/) from 3.6.10 to 4.0.4.

---
updated-dependencies:
- dependency-name: reportlab
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

requirements.txt

@@ -14,5 +14,5 @@ psycopg2==2.9.3
     # via -r requirements.in
 pytz==2019.3
     # via django
-reportlab==3.6.10
+reportlab==4.0.4
     # via -r requirements.in