Auto merge of #13836 - emilio:js-intl, r=Ms2ger

Update mozjs_sys to expose proper locale callbacks.

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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 #13788 (github issue number if applicable).

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- [ ] There are tests for these changes OR

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Fixes #13788

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tests/wpt/mozilla/meta/MANIFEST.json

@@ -7094,6 +7094,12 @@
             "url": "/_mozilla/mozilla/load_event.html"
           }
         ],
+        "mozilla/localeCompare.html": [
+          {
+            "path": "mozilla/localeCompare.html",
+            "url": "/_mozilla/mozilla/localeCompare.html"
+          }
+        ],
         "mozilla/mime_sniffing_font_context.html": [
           {
             "path": "mozilla/mime_sniffing_font_context.html",