Bug 1833417 - Add OSX Chromium-as-Release to cron. r=perftest-reviewers,taskgraph-reviewers,bhearsum,sparky

This patch updates the CaR cron with OSX builds.
Additionally, the time between building and running perftests is increased from 8 hours to 9 hours,
just to provide a bit more of a buffer in case of failures and in particular for OSX builds which take quite long.

Differential Revision: https://phabricator.services.mozilla.com/D180826

.cron.yml

@@ -117,7 +117,7 @@ jobs:
           - mozilla-central
       when:
           by-project:
-              mozilla-central: [{hour: 18, minute: 30}]
+              mozilla-central: [{hour: 20, minute: 30}]
 
     # For more context on this job, see:
     # https://github.com/mozsearch/mozsearch-mozilla#how-searchfoxorg-stays-up-to-date

taskcluster/gecko_taskgraph/target_tasks.py

@@ -1074,6 +1074,7 @@ def target_tasks_chromium_update(full_task_graph, parameters, graph_config):
         "fetch-mac-chromium",
         "toolchain-linux64-custom-car",
         "toolchain-win64-custom-car",
+        "toolchain-macosx64-custom-car",
     ]