Add "remoteAsyncEvents" and "sessionHistoryInParent" keywords in the …

…list of update_properties for wpt-update command.

Differential Revision: https://phabricator.services.mozilla.com/D229771

bugzilla-url: https://bugzilla.mozilla.org/show_bug.cgi?id=1932597
gecko-commit: c1a15d8f1a23b026bb4e33c2adf5871e41d9a776
gecko-reviewers: jgraham

tools/wptrunner/wptrunner/browsers/firefox.py

@@ -251,6 +251,8 @@ def update_properties():
         "swgl",
         "asan",
         "tsan",
+        "remoteAsyncEvents",
+        "sessionHistoryInParent",
         "subsuite"], {
         "os": ["version"],
         "processor": ["bits"]})