fix: docs website url

Author: juelg

index.html

@@ -136,7 +136,7 @@ <h1 class="title">
                 </span>
                 <!-- Doc link -->
                 <span class="link-block">
-                  <a href="https://robot-control-stack.org" target="_blank"
+                  <a href="https://robotcontrolstack.org" target="_blank"
                     class="external-link button is-normal is-rounded is-dark">
                     <span class="icon">
                       <i class="fas fa-book"></i>