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/web-platform-tests/html/semantics/forms/form-submission-0/submit-entity-body.html

@@ -96,7 +96,7 @@ function run_simple_test() {
   var testframe = document.getElementById("testframe");
   var testdocument = testframe.contentWindow.document;
   testdocument.body.innerHTML =
-    "<form id=testform method=post action=\"form-submission.py\" enctype=\"" + test_obj.enctype + "\">" +
+    "<form id=testform method=post action=\"form-submission.py?query=1\" enctype=\"" + test_obj.enctype + "\">" +
     test_obj.input +
     test_obj.submitelement +
     "</form>";