Use Matomo in https://arrow.apache.org/datafusion/

**Is your feature request related to a problem or challenge? Please describe what you are trying to do.**

Suggestion. If we want to analyze https://arrow.apache.org/datafusion/ , we can use Matomo provided by ASF.

https://arrow.apache.org/ uses Matome by apache/arrow-site#206, apache/arrow-site#215 and apache/arrow#13096 and we can see Matomo's dashboard for https://arrow.apache.org/ at https://analytics.apache.org/index.php?module=CoreHome&action=index&date=yesterday&period=day&idSite=20#?period=day&date=yesterday&category=Dashboard_Dashboard&subcategory=1 .

But this isn't required. If we don't need this for https://arrow.apache.org/datafusion/ , we can reject this suggestion.

**Describe the solution you'd like**

We can do it like apache/arrow#13096 :

```diff
diff --git a/docs/source/_templates/layout.html b/docs/source/_templates/layout.html
index a9d0f30b..ceadc26b 100644
--- a/docs/source/_templates/layout.html
+++ b/docs/source/_templates/layout.html
@@ -1,5 +1,28 @@
{% extends "pydata_sphinx_theme/layout.html" %}

+{# Use Matomo #}
+{% block extrahead %}
+ {{ super() }}
+
+
+
+ var _paq = window._paq = window._paq || [];
+ /* tracker methods like "setCustomDimension" should be called before "trackPageView" */
+ /* We explicitly disable cookie tracking to avoid privacy issues */
+ _paq.push(['disableCookies']);
+ _paq.push(['trackPageView']);
+ _paq.push(['enableLinkTracking']);
+ (function() {
+ var u="https://analytics.apache.org/";
+ _paq.push(['setTrackerUrl', u+'matomo.php']);
+ _paq.push(['setSiteId', '20']);
+ var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0];
+ g.async=true; g.src=u+'matomo.js'; s.parentNode.insertBefore(g,s);
+ })();
+
+
+{% endblock %}
+
{# Silence the navbar #}
{% block docs_navbar %}
{% endblock %}
```

**Describe alternatives you've considered**

I don't have any other idea.

**Additional context**

We must not use Google Analytics for this for becoming compliant with the GDPR (the European Union's General Data Protection Regulation):

* https://privacy.apache.org/policies/privacy-policy-public.html
* https://privacy.apache.org/faq/committers.html

If you're a PMC member, see also: https://lists.apache.org/thread/w7syx5v2kt3h7zmjqsw6hhpm6dq56bk7

Start with docs/source/_templates/layout.html and compare the proposed Matomo integration with the referenced apache/arrow#13096 change. Confirm that ASF permits tracking for the DataFusion site and that site ID 20 is appropriate; done means the generated DataFusion documentation pages include the approved privacy-preserving Matomo tracking.

Written by the indexing model from the issue text.