Bump gunicorn from 20.1.0 to 21.2.0

Bumps [gunicorn](https://github.com/benoitc/gunicorn) from 20.1.0 to 21.2.0.
- [Release notes](https://github.com/benoitc/gunicorn/releases)
- [Commits](benoitc/gunicorn@20.1.0...21.2.0)

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

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

requirements.in

@@ -18,7 +18,7 @@ django-storages==1.13.2
 django-tz-detect==0.4.0
 django-waffle==3.0.0
 dj-stripe==2.8.1
-gunicorn==20.1.0
+gunicorn==21.2.0
 psycopg2==2.9.6
 python-dateutil==2.8.2
 requests==2.31.0

requirements.txt

@@ -95,7 +95,7 @@ docutils==0.18.1
     #   sphinx-rtd-theme
 fonttools[woff]==4.34.4
     # via weasyprint
-gunicorn==20.1.0
+gunicorn==21.2.0
     # via -r requirements.in
 hashids==1.3.1
     # via django-hashid-field
@@ -116,7 +116,9 @@ markupsafe==2.1.1
 oauthlib==3.2.2
     # via requests-oauthlib
 packaging==21.3
-    # via sphinx
+    # via
+    #   gunicorn
+    #   sphinx
 pillow==9.3.0
     # via weasyprint
 psycopg2==2.9.6
@@ -237,6 +239,3 @@ whitenoise[brotli]==6.5.0
     # via -r requirements.in
 zopfli==0.2.1
     # via fonttools
-
-# The following packages are considered to be unsafe in a requirements file:
-# setuptools