Fix wpt failure in overwritten-customElements-global.html

Now only Node.js v18 fails, presumably due to improvements in Node.js itself.

test/web-platform-tests/to-run.yaml

@@ -372,7 +372,7 @@ form-associated/**: [fail-slow, Not implemented]
 htmlconstructor/newtarget-customized-builtins.html: [fail, unknown]
 htmlconstructor/newtarget.html: [fail, Currently impossible to get the active function associated realm]
 microtasks-and-constructors.html: [fail, Usage of external scripts doesn't block HTML parsing, https://github.com/jsdom/jsdom/issues/2413]
-overwritten-customElements-global.html: [fail, Unknown]
+overwritten-customElements-global.html: [fail-node18, Unknown]
 parser/parser-constructs-custom-element-in-document-write.html: [fail, Usage of external scripts doesn't block HTML parsing, https://github.com/jsdom/jsdom/issues/2413]
 parser/parser-constructs-custom-element-synchronously.html: [fail, Usage of external scripts doesn't block HTML parsing, https://github.com/jsdom/jsdom/issues/2413]
 parser/parser-fallsback-to-unknown-element.html: [fail, Usage of external scripts doesn't block HTML parsing, https://github.com/jsdom/jsdom/issues/2413]