HPCC-10989 Prevent "global" graph layout

The global layout will block the main layout and is not needed.

Fixes HPCC-10989

Signed-off-by: Gordon Smith <gordon.smith@lexisnexis.com>
Merge pull request #5516 from GordonSmith/HPCC-10989

HPCC-10989 Prevent "global" graph layout

Reviewed-By: Miguel Vazquez <miguel.vazquez@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>