docs: fix broken external reference URLs in examples#3898

mattijn merged 1 commit intovega:mainvega/altair:mainfrom

dsmedia:claude/fix-broken-example-urls-011CUWubDkmpTJZKvH6QMheUdsmedia/altair:claude/fix-broken-example-urls-011CUWubDkmpTJZKvH6QMheUCopy head branch name to clipboard