Add 1 additional shard to Mac13-Tests due to longer runtimes.

Bug: 1458501
Change-Id: I91ca1c10a5d2bf26bf5fcc29957ace88acabd309
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4650591
Reviewed-by: Struan Shrimpton <[email protected]>
Commit-Queue: Lindsay Pasricha <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1163181}
diff --git a/testing/buildbot/test_suite_exceptions.pyl b/testing/buildbot/test_suite_exceptions.pyl
index 2b5d470..088d647 100644
--- a/testing/buildbot/test_suite_exceptions.pyl
+++ b/testing/buildbot/test_suite_exceptions.pyl
@@ -4191,6 +4191,11 @@
           '--test-launcher-filter-file=../../testing/buildbot/filters/ozone-linux.unit_tests_wayland.filter',
         ],
       },
+      'Mac13 Tests': {
+        'swarming': {
+          'shards': 2,
+        },
+      },
       'Mac13 Tests (dbg)': {
         'swarming': {
           'shards': 2,