Clear space before generating the beam site pr - it seems this takes … (#35355)

* Clear space before generating the beam site pr - it seems this takes a lot of disk space somehow

* Dont clear docker image used by javadoc action

Author: damccorm

.github/workflows/build_release_candidate.yml

@@ -306,6 +306,10 @@ jobs:
       BEAM_ROOT_DIR: ${{ github.workspace }}/beam
       SITE_ROOT_DIR: ${{ github.workspace }}/beam-site
     steps:
+      - name: Free Disk Space (Ubuntu)
+        uses: jlumbroso/free-disk-space@v1.3.0
+        with:
+          docker-images: false
       - name: Checkout Beam Repo
         uses: actions/checkout@v4
         with: