Bump towncrier from 23.11.0 to 25.8.0

Bumps [towncrier](https://github.com/twisted/towncrier) from 23.11.0 to 25.8.0.
- [Release notes](https://github.com/twisted/towncrier/releases)
- [Changelog](https://github.com/twisted/towncrier/blob/trunk/NEWS.rst)
- [Commits](twisted/towncrier@23.11.0...25.8.0)

---
updated-dependencies:
- dependency-name: towncrier
  dependency-version: 25.8.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

requirements/towncrier.txt

@@ -1 +1 @@
-towncrier==23.11.0
+towncrier==25.8.0