Add free-disk-space step

Author: friedemannf

.github/workflows/aptos-ccip-tests.yml

@@ -22,6 +22,9 @@ jobs:
       DEFAULT_CORE_REF: develop
       GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
     steps:
+      - name: Free up disk space
+        uses: smartcontractkit/.github/actions/free-disk-space@free-disk-space/v1
+
       - name: Get core ref from PR body
         if: github.event_name == 'pull_request'
         run: |