Bug 1648851 - reduce max-run-time value of android-api-16-shippable/opt task to 1800 r=gbrown,jmaher

Changes:
  - max-run-time reduced to 1800 which should suffice.

Differential Revision: https://phabricator.services.mozilla.com/D82253

taskcluster/ci/generate-profile/kind.yml

@@ -93,7 +93,7 @@ jobs:
             platform: android-4-0-armv7-api16/pgo
         worker-type: t-linux-xlarge-pgo
         worker:
-            max-run-time: 5400
+            max-run-time: 1800
             docker-image: {in-tree: ubuntu1804-test}
             env:
                 WORKING_DIR: "/builds/worker"