Update docs to version 6.10

Amp-Thread-ID: https://ampcode.com/threads/T-42a73a57-4b39-4ba8-b672-a157280e168a
Co-authored-by: Amp <[email protected]>

Author: enriquegh

docs.config.js

@@ -1,5 +1,5 @@
 const config = {
-	DOCS_LATEST_VERSION: '6.9'
+	DOCS_LATEST_VERSION: '6.10'
 };
 
 module.exports = config;

docs/legacy.mdx

@@ -4,6 +4,7 @@
 
 <Accordion title="Sourcegraph 6.X">
 
+  - [6.9](https://6.9.sourcegraph.com)
   - [6.8](https://6.8.sourcegraph.com)
   - [6.7](https://6.7.sourcegraph.com)
   - [6.6](https://6.6.sourcegraph.com)

src/data/versions.ts

@@ -14,6 +14,10 @@ export const versions: VersionI[] = [
         label: 'latest',
         url: '/docs',
     },
+    {
+        name: 'v6.9',
+        url: 'https://6.9.sourcegraph.com/'
+    },
     {
         name: 'v6.8',
         url: 'https://6.8.sourcegraph.com/'