Build(deps): Bump cython from 3.1.6 to 3.2.1 (#720)

Bumps [cython](https://github.com/cython/cython) from 3.1.6 to 3.2.1.
- [Release notes](https://github.com/cython/cython/releases)
- [Changelog](https://github.com/cython/cython/blob/master/CHANGES.rst)
- [Commits](cython/cython@3.1.6...3.2.1)

---
updated-dependencies:
- dependency-name: cython
  dependency-version: 3.2.1
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements/cython.txt

@@ -1 +1 @@
-cython==3.1.6
+cython==3.2.1