fix: Ensure GitHub app token is created for both "apidocs" and "preview.apidocs"

This addresses the following error when attempting to push the branch
into the "preview.apidocs.slicer.org" repository:

> remote: Permission to Slicer/preview.apidocs.slicer.org.git denied to slicer-app[bot].
> fatal: unable to access 'https://github.com/Slicer/preview.apidocs.slicer.org/': The requested URL returned error: 403

Author: jcfr

.github/workflows/doxygen-build-and-publish.yml

@@ -180,6 +180,10 @@ jobs:
         with:
           app-id: ${{ vars.SLICER_APP_ID }}
           private-key: ${{ secrets.SLICER_APP_PRIVATE_KEY }}
+          owner: Slicer
+          repositories: |
+            apidocs.slicer.org
+            preview.apidocs.slicer.org
 
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with: