fix(deps): update dependency django to v4.2.21 [security] (#2234)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

poetry.lock

@@ -22,7 +22,7 @@ cffi = "^1.15.1"
 cryptography = "^44.0.0"
 dj-database-url = "^2.0.0"
 dj-static = "^0.0.6"
-Django = "4.2.20"
+Django = "4.2.21"
 django-anymail = {extras = ["mailgun"], version = "^12.0"}
 django-bitfield = "^2.2.0"
 django-cache-memoize = "^0.2.0"