fix(ci): try tmpfs mount

sidestep fs limitation for exist/data

.github/workflows/build.yml

@@ -74,6 +74,7 @@ jobs:
         run: |
           docker run -dit -p 8080:8080 -v ${{ github.workspace }}/build:/exist/autodeploy \
           --name exist --rm \
+          --mount type=tmpfs,destination=/exist/data \
           duncdrum/existdb:${{ matrix.exist-version }}
       
       - name: wait for install to finish