Promote LibCyphal to beta

Author: pavel-kirienko

app/templates/home/content-column.html

@@ -131,7 +131,7 @@ <h1 id="how">How do I use Cyphal?</h1>
         <td>Cyphal/UDP, Cyphal/CAN</td>
         <td>C++</td>
         <td>Embedded (higher-level), application</td>
-        <td>Work in progress</td>
+        <td>Beta</td>
       </tr>
       <tr>
         <td><a href="https://github.com/OpenCyphal/pycyphal">PyCyphal</a></td>