Use single plausible analytics script. (#1209)

[Enable "Outbound
links"](https://plausible.io/docs/outbound-link-click-tracking)

Author: nikoshell

src/components/BaseHead.astro

@@ -52,12 +52,6 @@ const { title, description, image = "/social-card.png" } = Astro.props;
 <meta http-equiv="X-Clacks-Overhead" content="GNU Oier Etxaniz" />
 <meta http-equiv="X-Clacks-Overhead" content="GNU Russel Winder" />
 
-<script
-  defer
-  is:inline
-  data-domain="ep2025.europython.eu"
-  src="https://plausible.io/js/script.js"></script>
-
 <script
   defer
   is:inline