build(deps): update django-csp requirement

Updates the requirements on [django-csp](https://github.com/mozilla/django-csp) to permit the latest version.

Updates `django-csp` to 4.0
- [Release notes](https://github.com/mozilla/django-csp/releases)
- [Changelog](https://github.com/mozilla/django-csp/blob/main/CHANGES.md)
- [Commits](mozilla/django-csp@3.8...v4.0)

---
updated-dependencies:
- dependency-name: django-csp
  dependency-version: '4.0'
  dependency-type: direct:production
  dependency-group: django-extensions
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

pyproject.toml

@@ -37,7 +37,7 @@ dependencies = [
     "courts-db>=0.10.17",
     "cryptography>=44.0.1",
     "disposable-email-domains>=0.0.90",
-    "django-csp~=3.8",
+    "django-csp~=4.0",
     "django-environ>=0.12.0",
     "django-hcaptcha>=0.2.0",
     "django-htmx>=1.23.0",