Update dawidd6/action-download-artifact action to v15

Author: renovate[bot]

.github/workflows/vortex-test-docs.yml

@@ -44,7 +44,7 @@ jobs:
           php-version: 8.3
 
       - name: Download installer artifact
-        uses: dawidd6/action-download-artifact@5c98f0b039f36ef966fdb7dfa9779262785ecb05 # v14
+        uses: dawidd6/action-download-artifact@fe9d59ce33ce92db8a6ac90b2c8be6b6d90417c8 # v15
         with:
           workflow: vortex-test-installer.yml
           name: vortex-installer