LUCI migration: remove Mac Builder (dbg) from migration console.

R=hinoka@chromium.org

Bug: 790154, 790169
Change-Id: I168f5b9a321ec31ae651a76ca6e629b2e592a988
No-Try: True
Reviewed-on: https://chromium-review.googlesource.com/947705
Commit-Queue: Andrii Shyshkalov <tandrii@chromium.org>
Reviewed-by: Ryan Tseng <hinoka@chromium.org>
Cr-Commit-Position: refs/heads/master@{#542363}

infra/config/global/luci-milo.cfg

@@ -1559,17 +1559,6 @@ consoles: {
     short_name: "bb"
   }
 
-  builders: {
-    name: "buildbucket/luci.chromium.ci/Mac Builder (dbg)"
-    category: "mac|debug|builder"
-    short_name: "ci"
-  }
-  builders: {
-    name: "buildbot/chromium.mac/Mac Builder (dbg)"
-    category: "mac|debug|builder"
-    short_name: "bb"
-  }
-
   builders: {
     name: "buildbucket/luci.chromium.ci/WebKit Mac Builder (dbg)"
     category: "webkit|mac|debug|builder"