docs: fix broken Observable URL in Top-K example#9705

dsmedia wants to merge 1 commit intovega:mainvega/vega-lite:mainfrom

dsmedia:claude/fix-observable-url-011CUWtZ73HiLGif2D4aB8KLdsmedia/vega-lite:claude/fix-observable-url-011CUWtZ73HiLGif2D4aB8KLCopy head branch name to clipboard