servo: Merge #13589 - Support SVG element (from splav:SVGElement#12974); r=pcwalton,Ms2ger

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minimal SVG element implementation
---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #12974 (github issue number if applicable).

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- [x] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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Source-Repo: https://github.com/servo/servo
Source-Revision: dad3b4785a73aa6ddea5ed50ee4ef01bd4049c8d

servo/python/tidy/servo_tidy/tidy.py

@@ -70,6 +70,7 @@ WEBIDL_STANDARDS = [
     "//w3c.github.io",
     "//heycam.github.io/webidl",
     "//webbluetoothcg.github.io/web-bluetooth/",
+    "//svgwg.org/svg2-draft",
     # Not a URL
     "// This interface is entirely internal to Servo, and should not be" +
     " accessible to\n// web pages."