Bump djangorestframework from 3.8.2 to 3.11.2 in /meron_api/requirements

Bumps [djangorestframework](https://github.com/encode/django-rest-framework) from 3.8.2 to 3.11.2.
- [Release notes](https://github.com/encode/django-rest-framework/releases)
- [Commits](encode/django-rest-framework@3.8.2...3.11.2)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

meron_api/requirements/base.txt

@@ -1,6 +1,6 @@
 Django==2.2.19
 django-environ==0.4.5
-djangorestframework==3.9.4
+djangorestframework==3.11.2
 dlib==19.21.1
 imutils==0.5.4
 joblib==1.0.1