Bug 1966215 [wpt PR 52509] - Summarizer API: Fix summarizeStreaming WPT,

Automatic update from web-platform-tests
Summarizer API: Fix summarizeStreaming WPT

Check the concatenated text stream, rather than the last chunk.

Fixed: 417493972
Change-Id: Ia3fde37e011efff04a431e4ef61a3c4d2f3015ad
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6542867
Auto-Submit: Mike Wasserman <mswchromium.org>
Commit-Queue: Mike Wasserman <mswchromium.org>
Reviewed-by: Daseul Lee <dsleechromium.org>
Commit-Queue: Daseul Lee <dsleechromium.org>
Cr-Commit-Position: refs/heads/main{#1459650}

--

wpt-commits: f7e886ebf1bbd6d70af660bdd126fd3238f63274
wpt-pr: 52509

Differential Revision: https://phabricator.services.mozilla.com/D250157

UltraBlame original commit: 80cfddeb9fd202058182ba30645acee12dc4362c

Author: marco-c

testing/web-platform/tests/ai/summarizer/summarizer-summarize-streaming.tentative.https.window.js

@@ -231,6 +231,7 @@ break
 ;
 }
 result
++
 =
 value
 ;