Auto merge of #22354 - jdm:ddg, r=Manishearth

Fix DuckDuckGo HTML search

- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #22090
- [x] There are tests for these changes

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tests/wpt/metadata/MANIFEST.json

@@ -454007,7 +454007,7 @@
    "support"
   ], 
   "common/form-submission.py": [
-   "467875453c9dc64aac51add3f4a617d941820972", 
+   "b296ac44c57c658ca9e3189e9f79b0f80677acba", 
    "support"
   ], 
   "common/get-host-info.sub.js": [
@@ -626623,7 +626623,7 @@
    "testharness"
   ], 
   "html/semantics/forms/form-submission-0/submit-entity-body.html": [
-   "8363f39ff32cd165a28086b3c594b55a79ced8e5", 
+   "a52bb0dcd2080eabb44ab1ddca379da6a5e5ea9a", 
    "testharness"
   ], 
   "html/semantics/forms/form-submission-0/submit-file.sub.html": [