[test] Format new _connectionId field as type in web tests.

Bug: 374288085
Change-Id: I7f2d20d9ffc540017608a626eb05da2b21d3007d
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/5946884
Reviewed-by: Yang Guo <[email protected]>
Auto-Submit: Benedikt Meurer <[email protected]>
Commit-Queue: Yang Guo <[email protected]>

Author: bmeurer

front_end/legacy_test_runner/network_test_runner/network_test_runner.js

@@ -195,6 +195,7 @@ NetworkTestRunner.HARPropertyFormatters = {
   timings: 'formatAsTypeName',
   version: 'formatAsTypeName',
   wait: 'formatAsTypeName',
+  _connectionId: 'formatAsTypeName',
   _transferSize: 'formatAsTypeName',
   _error: 'skip',
   _initiator: 'formatAsTypeName',