chore(deps): update pytest-mock requirement in /bots/gsbot

Updates the requirements on [pytest-mock](https://github.com/pytest-dev/pytest-mock) to permit the latest version.
- [Release notes](https://github.com/pytest-dev/pytest-mock/releases)
- [Changelog](https://github.com/pytest-dev/pytest-mock/blob/main/CHANGELOG.rst)
- [Commits](pytest-dev/pytest-mock@v3.12.0...v3.15.1)

---
updated-dependencies:
- dependency-name: pytest-mock
  dependency-version: 3.15.1
  dependency-type: direct:production
...

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

Author: dependabot[bot]

bots/gsbot/requirements.txt

@@ -21,7 +21,7 @@ cachetools>=6.2.6
 pytest>=8.4.2
 pytest-asyncio>=0.21.1
 pytest-cov>=7.1.0
-pytest-mock>=3.12.0
+pytest-mock>=3.15.1
 
 # Code Quality
 black>=25.11.0