Update docs to version 6.8 (#1360)

Updates documentation to version 6.8

Author: enriquegh

docs.config.js

@@ -1,5 +1,5 @@
 const config = {
-	DOCS_LATEST_VERSION: '6.7'
+	DOCS_LATEST_VERSION: '6.8'
 };
 
 module.exports = config;

docs/legacy.mdx

@@ -4,6 +4,7 @@
 
 <Accordion title="Sourcegraph 6.X">
 
+  - [6.7](https://6.7.sourcegraph.com)
   - [6.6](https://6.6.sourcegraph.com)
   - [6.5](https://6.5.sourcegraph.com)
   - [6.4](https://6.4.sourcegraph.com)

src/data/versions.ts

@@ -15,8 +15,8 @@ export const versions: VersionI[] = [
         url: '/docs',
     },
     {
-        name: 'v6.6',
-        url: 'https://6.6.sourcegraph.com/'
+        name: 'v6.7',
+        url: 'https://6.7.sourcegraph.com/'
     },
 ];