test: fix WPT title when no META title is present

PR-URL: https://github.com/nodejs/node/pull/46804
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Richard Lau <rlau@redhat.com>

test/common/wpt.js

@@ -721,7 +721,7 @@ class WPTRunner {
 
   getTestTitle(filename) {
     const spec = this.specMap.get(filename);
-    return spec.meta?.title || filename;
+    return spec.meta?.title || filename.split('.')[0];
   }
 
   // Map WPT test status to strings