Update troubleshooting.mdx (#888)

Add troubleshooting note to Cody troubleshooting about adding forked
repos as context

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docs/cody/troubleshooting.mdx

@@ -224,6 +224,10 @@ $filteredResults = preg_grep('*\.' . basename($inputPath) . '\.*', $fileList);
 ```
 ````
 
+## Forked Repos As Context
+
+If you would like to add a forked repository as Cody context, you may need to add `"search.includeForks": true` to the [global settings](/admin/config/settings#editing-global-settings-for-site-admins) for your instance.
+
 ## Eclipse extension
 
 ### See a white screen the first time you open Cody chat