chore: bump pip from 24.2 to 25.3 in /requirements

Bumps [pip](https://github.com/pypa/pip) from 24.2 to 25.3.
- [Changelog](https://github.com/pypa/pip/blob/main/NEWS.rst)
- [Commits](pypa/pip@24.2...25.3)

---
updated-dependencies:
- dependency-name: pip
  dependency-version: '25.3'
  dependency-type: direct:production
...

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

Author: dependabot[bot]

requirements/constraints.txt

@@ -9,4 +9,4 @@
 # linking to it here is good.
 
 # https://github.com/jazzband/pip-tools/issues/2131
-pip==24.2
+pip==25.3