docs: Update metrics (#3277)

Author: kyleconroy

docs/_templates/layout.html

@@ -1,6 +1,6 @@
 {% extends "!layout.html" %}
 
 {% block extrahead %}
-<script defer data-domain="docs.sqlc.dev" src="https://plausible.io/js/plausible.js"></script>
+<script defer data-domain="docs.sqlc.dev" data-api="https://proxy.sqlc.dev/api/event" src="https://proxy.sqlc.dev/js/script.js"></script>
 {{ super() }}
-{% endblock %}
+{% endblock %}