Bump pytest from 8.3.4 to 9.0.3 in /packages/typespec-python

Bumps [pytest](https://github.com/pytest-dev/pytest) from 8.3.4 to 9.0.3.
- [Release notes](https://github.com/pytest-dev/pytest/releases)
- [Changelog](https://github.com/pytest-dev/pytest/blob/main/CHANGELOG.rst)
- [Commits](pytest-dev/pytest@8.3.4...9.0.3)

---
updated-dependencies:
- dependency-name: pytest
  dependency-version: 9.0.3
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

packages/typespec-python/dev_requirements.txt

@@ -5,7 +5,7 @@ tox==4.23.2
 mypy==1.13.0
 colorama==0.4.6
 debugpy==1.8.12
-pytest==8.3.4
+pytest==9.0.3
 coverage==7.6.1
 black==24.8.0
 ptvsd==4.3.2