Bump actions/setup-python from 4 to 5 in /.github/actions/build-vsix

Bumps [actions/setup-python](https://github.com/actions/setup-python) from 4 to 5.
- [Release notes](https://github.com/actions/setup-python/releases)
- [Commits](actions/setup-python@v4...v5)

---
updated-dependencies:
- dependency-name: actions/setup-python
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/actions/build-vsix/action.yml

@@ -23,7 +23,7 @@ runs:
 
     # Jedi LS depends on dataclasses which is not in the stdlib in Python 3.7.
     - name: Use Python 3.8 for JediLSP
-      uses: actions/setup-python@v4
+      uses: actions/setup-python@v5
       with:
         python-version: 3.8
         cache: 'pip'