Auto merge of #12365 - simartin:issue_12071, r=KiChjang

Issue #12071: Don't submit forms when typing Tab on an input.

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Fixes https://github.com/servo/servo/issues/12071
---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #12071

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- [X] There are tests for these changes

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tests/wpt/mozilla/meta/MANIFEST.json

@@ -6504,6 +6504,12 @@
             "url": "/_mozilla/mozilla/form_submit_about.html"
           }
         ],
+        "mozilla/form_tab_keyevent.html": [
+          {
+            "path": "mozilla/form_tab_keyevent.html",
+            "url": "/_mozilla/mozilla/form_tab_keyevent.html"
+          }
+        ],
         "mozilla/getBoundingClientRect.html": [
           {
             "path": "mozilla/getBoundingClientRect.html",