build(deps): bump celery from 4.4.6 to 4.4.7

Bumps [celery](https://github.com/celery/celery) from 4.4.6 to 4.4.7.
- [Release notes](https://github.com/celery/celery/releases)
- [Changelog](https://github.com/celery/celery/blob/master/Changelog.rst)
- [Commits](https://github.com/celery/celery/compare/v4.4.6...v4.4.7)

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

Pipfile.lock

@@ -61,11 +61,11 @@
         },
         "celery": {
             "hashes": [
-                "sha256:ef17d7dffde7fc73ecab3a3b6389d93d3213bac53fa7f28e68e33647ad50b916",
-                "sha256:fd77e4248bb1b7af5f7922dd8e81156f540306e3a5c4b1c24167c1f5f06025da"
+                "sha256:a92e1d56e650781fb747032a3997d16236d037c8199eacd5217d1a72893bca45",
+                "sha256:d220b13a8ed57c78149acf82c006785356071844afe0b27012a4991d44026f9f"
             ],
             "index": "pypi",
-            "version": "==4.4.6"
+            "version": "==4.4.7"
         },
         "certifi": {
             "hashes": [