Add v8testing to v8_mac_arm64_rel_ng_triggered

Bug: chromium:1110824
Change-Id: Ibc914d0261d09cf3a15fd01d0e9df0868d773fce
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2343328Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Almothana Athamneh <almuthanna@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69304}

infra/testing/builders.pyl

@@ -633,7 +633,9 @@
       'cpu': 'x86-64',
       'os': 'Mac-10.13',
     },
-    'tests': [],
+    'tests': [
+      {'name': 'v8testing'},
+    ],
   },
   ##############################################################################
   ### luci.v8.ci