Karma: apply patch to prevent timeouts after test complete

In github.com/karma-runner/karma/pull/3852 it is suggested that the 30s
timeout issue with Karma can be seen when:

1. All the tests complete, which sets the state of Karma to
   "disconnected"
2. But there is some async activity which logs, or something. This
   causes Karma to restart its 30s timeout, but no more messages will be
   received.

This is a bit experimental, but trying this patch to see if it has a
positive impact on CQ.

Bug: 406729910
Change-Id: Iaaa9247c801e193e5782a0da4857d804bcc45a92
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/6407593
Auto-Submit: Jack Franklin <[email protected]>
Reviewed-by: Simon Zünd <[email protected]>
Commit-Queue: Jack Franklin <[email protected]>

Author: jackfranklin