Bump pkgxdev/setup from 2 to 4 (#79)

Bumps [pkgxdev/setup](https://github.com/pkgxdev/setup) from 2 to 4.
- [Release notes](https://github.com/pkgxdev/setup/releases)
- [Commits](pkgxdev/setup@v2...v4)

---
updated-dependencies:
- dependency-name: pkgxdev/setup
  dependency-version: '4'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/windows-pkgx.yml

@@ -21,7 +21,7 @@ jobs:
           submodules: true
 
       - name: Setup Clang
-        uses: pkgxdev/setup@v2
+        uses: pkgxdev/setup@v4
         with:
           +: clang@19