➕ feat(amp): Add amp-consent extension to default layout

This commit introduces the `amp-consent` extension into the HEAD element of the `_layouts/default.html` template file in our Jekyll theme.

The addition of the `amp-consent` extension is a crucial step towards the development of a fully functional cookie consent notice. This extension enables the cookie consent notice to display appropriately and collect user consent effectively.

This change ensures that our Jekyll theme is compliant with user consent requirements.

See: ✨ Add Cookie Consent Notice Banner 🍪 #44

_layouts/default.html

@@ -7,6 +7,7 @@
     {% seo %}
     <link as="script" href="https://cdn.ampproject.org/v0.js" rel="preload">
     <script async src="https://cdn.ampproject.org/v0.js"></script>
+    <script async custom-element="amp-consent" src="https://cdn.ampproject.org/v0/amp-consent-0.1.js"></script>
     <script async custom-element="amp-analytics" src="https://cdn.ampproject.org/v0/amp-analytics-0.1.js"></script>
     {%- if site.adsense.client_id and site.adsense.auto_ads != false -%}
     <script async custom-element="amp-auto-ads" src="https://cdn.ampproject.org/v0/amp-auto-ads-0.1.js"></script>