MINOR: Update version to 4.1 in docs

Author: mimaison

docs/documentation.html

@@ -33,7 +33,7 @@
     <!--//#include virtual="../includes/_docs_banner.htm" -->
 
     <h1>Documentation</h1>
-    <h3>Kafka 4.0 Documentation</h3>
+    <h3>Kafka 4.1 Documentation</h3>
     Prior releases: <a href="/07/documentation.html">0.7.x</a>, 
                     <a href="/08/documentation.html">0.8.0</a>, 
                     <a href="/081/documentation.html">0.8.1.X</a>, 
@@ -64,6 +64,7 @@ <h3>Kafka 4.0 Documentation</h3>
                     <a href="/37/documentation.html">3.7.X</a>,
                     <a href="/38/documentation.html">3.8.X</a>,
                     <a href="/39/documentation.html">3.9.X</a>.
+                    <a href="/40/documentation.html">4.0.X</a>.
 
    <h2 class="anchor-heading"><a id="gettingStarted" class="anchor-link"></a><a href="#gettingStarted">1. Getting Started</a></h2>
       <h3 class="anchor-heading"><a id="introduction" class="anchor-link"></a><a href="#introduction">1.1 Introduction</a></h3>