Copy and follow symlinks in run_explain_suite pipeline

This allows us to reduce code duplication of workload SQL scripts

concourse/tasks/run_explain_suite.yml

@@ -26,7 +26,7 @@ run:
       if [[ "${i}" = "all" || "${i}" = "${WORKLOAD}" ]]
       then
         echo "Running workload ${WORKLOAD}"
-        cp -r gp_workloads/${WORKLOAD}/sql sql
+        cp -rL gp_workloads/${WORKLOAD}/sql sql
         cp gp_workloads/${WORKLOAD}/schema_6X.sql schema.sql
         cp gp_workloads/${WORKLOAD}/stats_6X.sql stats.sql
         gpdb_src/concourse/scripts/build_gpdb.py --mode ${MODE} --action test_explain_suite