Bug 1618206 - Update test expectation of update-and-send-events-replacement.html. r=hiro

The setter of Animation.timeline is supported only on Nightly.

Differential Revision: https://phabricator.services.mozilla.com/D64440

--HG--
extra : moz-landing-system : lando

testing/web-platform/meta/web-animations/timing-model/timelines/update-and-send-events-replacement.html.ini

@@ -5,3 +5,23 @@
     expected:
       if (os == "android") and debug: [PASS, TIMEOUT]
 
+  [Removes an animation after updating another animation's timeline]
+    expected:
+      if not nightly_build: FAIL
+
+  [Removes an animation after updating its timeline]
+    expected:
+      if not nightly_build: FAIL
+
+  [Does NOT remove an animation after making a redundant change to another animation's timeline]
+    expected:
+      if not nightly_build: FAIL
+
+  [Does NOT remove an animation after making a redundant change to its timeline]
+    expected:
+      if not nightly_build: FAIL
+
+  [Updates ALL timelines before checking for replacement]
+    expected:
+      if not nightly_build: FAIL
+