Add package link to tracker.debian.org

This makes it easier to check the Debian's package status.

Signed-off-by: Dylan Aïssi <dylan.aissi@collabora.com>

templates/index.html.jinja2

@@ -240,6 +240,9 @@
       <div class="d-flex w-100 justify-content-between">
         <h5 class="mb-1">
           <strong>
+            {%- if "upstreams" in package %}
+            <a href="https://tracker.debian.org/pkg/{{ package.name }}">🍥</a>
+            {% endif -%}
             {%- if "git" in package %}
             <a class="text-dark" href="{{ package.git.web_url }}">{{ package.name }}</a>
             {% else %}