[docs] Apply changes to 270 release (apache#8852)

### Motivation
Sync changes from apache#8762

site2/website/versioned_docs/version-2.7.0/client-libraries-websocket.md

@@ -1,14 +1,13 @@
 ---
 id: version-2.7.0-client-libraries-websocket
-title: Pulsar's WebSocket API
+title: Pulsar WebSocket API
 sidebar_label: WebSocket
 original_id: client-libraries-websocket
 ---
 
-Pulsar's [WebSocket](https://developer.mozilla.org/en-US/docs/Web/API/WebSockets_API) API is meant to provide a simple way to interact with Pulsar using languages that do not have an official [client library](getting-started-clients.md). Through WebSockets you can publish and consume messages and use all the features available in the [Java](client-libraries-java.md), [Go](client-libraries-go.md), [Python](client-libraries-python.md) and [C++](client-libraries-cpp.md) client libraries.
+Pulsar [WebSocket](https://developer.mozilla.org/en-US/docs/Web/API/WebSockets_API) API provides a simple way to interact with Pulsar using languages that do not have an official [client library](getting-started-clients.md). Through WebSocket, you can publish and consume messages and use features available on the [Client Features Matrix](https://github.com/apache/pulsar/wiki/Client-Features-Matrix) page.
 
-
-> You can use Pulsar's WebSocket API with any WebSocket client library. See examples for Python and Node.js [below](#client-examples).
+> You can use Pulsar WebSocket API with any WebSocket client library. See examples for Python and Node.js [below](#client-examples).
 
 ## Running the WebSocket service
 

site2/website/versioned_docs/version-2.7.0/getting-started-clients.md

@@ -1,7 +1,7 @@
 ---
 id: version-2.7.0-client-libraries
 title: Pulsar client libraries
-sidebar_label: Use Pulsar with client libraries
+sidebar_label: Overview
 original_id: client-libraries
 ---
 

site2/website/versioned_sidebars/version-2.7.0-sidebars.json

@@ -105,6 +105,7 @@
       "version-2.7.0-performance-pulsar-perf"
     ],
     "Client libraries": [
+      "version-2.7.0-client-libraries",
       "version-2.7.0-client-libraries-java",
       "version-2.7.0-client-libraries-go",
       "version-2.7.0-client-libraries-python",