[tools] Add CQ config for header include trybot

R=machenbach@chromium.org

No-Try: true
No-Tree-Checks: true
Bug: v8:7966
Change-Id: I662a693a2c2334113093fa0d3730ce71712f7cc8
Reviewed-on: https://chromium-review.googlesource.com/1148043Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Sergiy Byelozyorov <sergiyb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54624}

infra/config/cq.cfg

@@ -36,6 +36,10 @@ verifiers {
         triggered_by: "v8_linux64_dbg_ng"
       }
       builders { name: "v8_linux64_gcc_compile_dbg" }
+      builders {
+        name: "v8_linux64_header_includes_dbg"
+        experiment_percentage: 100
+      }
       builders { name: "v8_linux64_jumbo_compile_rel" }
       builders { name: "v8_linux64_rel_ng" }
       builders {