Add goma debug flag to Mac ASan 64 Builder

bug: b/110702574, 855396
Change-Id: I3be9d02d2ed07b39bfa10535f3cafee86e01d044
Reviewed-on: https://chromium-review.googlesource.com/1112871
Commit-Queue: Ryan Tseng <hinoka@chromium.org>
Reviewed-by: Andrii Shyshkalov <tandrii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#570094}

infra/config/global/cr-buildbucket.cfg

@@ -1582,6 +1582,10 @@ buckets {
       dimensions: "os:Mac-10.13"
       dimensions: "cores:"  # Swapping between 8 and 24
       mixins: "memory-ci"
+      # TODO(hinoka): Remove this after debugging.
+      recipe {
+        properties_j: "$build/goma:{\"debug\": true}"
+      }
     }
     builders {
       name: "UBSan Release"