Mark two idlharness tests as timeout=long

On Chromium CI these are occasionally spiking to 7s, causing timeouts.

Bug: 1062667
Change-Id: Ib4d21732c74c14b83b492945314813eff0f8c36b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2110523
Commit-Queue: Robert Ma <robertma@chromium.org>
Reviewed-by: Robert Ma <robertma@chromium.org>
Cr-Commit-Position: refs/heads/master@{#752016}

third_party/blink/web_tests/TestExpectations

@@ -6651,8 +6651,6 @@ crbug.com/1058403 external/wpt/webaudio/the-audio-api/the-audioworklet-interface
 
 crbug.com/1057020 [ Fuchsia ] http/tests/streams/chromium/get-reader-byob.html [ Pass Timeout ]
 
-crbug.com/1062667 [ Mac ] external/wpt/server-timing/idlharness.https.any.html [ Pass Timeout ]
-
 # Sheriff 2020-03-05
 crbug.com/1058073 [ Retina ] virtual/threaded/fast/scroll-snap/snap-to-target-on-layout-change.html [ Pass Failure ]
 crbug.com/1058073 [ Mac10.14 ] accessibility/content-changed-notification-causes-crash.html [ Pass Failure ]

third_party/blink/web_tests/external/wpt/server-timing/idlharness.https.any.js

 // META: script=/resources/WebIDLParser.js
 // META: script=/resources/idlharness.js
+// META: timeout=long
 
 'use strict';
 

third_party/blink/web_tests/external/wpt/uievents/idlharness.window.js

 // META: script=/resources/WebIDLParser.js
 // META: script=/resources/idlharness.js
+// META: timeout=long
 
 'use strict';