Bump celery from 4.4.6 to 5.2.2 in /requirements

Bumps [celery](https://github.com/celery/celery) from 4.4.6 to 5.2.2. - [Release notes](https://github.com/celery/celery/releases) - [Changelog](https://github.com/celery/celery/blob/master/Changelog.rst) - [Commits](celery/celery@v4.4.6...v5.2.2) --- updated-dependencies: - dependency-name: celery dependency-type: direct:production ... Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

requirements/base.txt

@@ -1,4 +1,4 @@
-celery==4.4.6 # pyup: <5.0
+celery==5.2.2 # pyup: <5.0
 Django==2.2.19 # pyup: <3.0
 django-cleanup==5.1.0
 django_compressor==2.4