Build(deps): Bump actions/download-artifact from 3 to 4

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 3 to 4.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v3...v4)

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

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

.github/workflows/ci_cd.yml

@@ -123,7 +123,7 @@ jobs:
           repository: ansys-internal/signtool-ansys-apps
           token: ${{ secrets.SIGNTOOL_ACCESS_TOKEN }}
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Python-Installer
           path: signtool/installer
@@ -154,12 +154,12 @@ jobs:
     needs: [sign-application]
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Python-Installer-Signed
           path: installer-signed
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Python-Installer
           path: installer