Bump python-dotenv from 0.20.0 to 0.21.0

Bumps [python-dotenv](https://github.com/theskumar/python-dotenv) from 0.20.0 to 0.21.0.
- [Release notes](https://github.com/theskumar/python-dotenv/releases)
- [Changelog](https://github.com/theskumar/python-dotenv/blob/main/CHANGELOG.md)
- [Commits](https://github.com/theskumar/python-dotenv/compare/v0.20.0...v0.21.0)

---
updated-dependencies:
- dependency-name: python-dotenv
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

requirements.txt

@@ -6,7 +6,7 @@ django-cleanup==6.0.0
 django-crispy-forms==1.14.0
 django-tables2==2.4.1
 djangorestframework==3.13.1
-drf-writable-nested==0.6.4
+drf-writable-nested==0.7.0
 django-oauth-toolkit==2.1.0
 bleach==5.0.1
 bleach-allowlist==1.0.3
@@ -15,7 +15,7 @@ lxml==4.9.1
 Markdown==3.3.7
 Pillow==9.1.1
 psycopg2-binary==2.9.3
-python-dotenv==0.20.0
+python-dotenv==0.21.0
 requests==2.28.1
 six==1.16.0
 webdavclient3==3.14.6