content: usage: advanced: fix broken link

Author: ES-Alexander

content/usage/advanced/index.md

@@ -349,7 +349,7 @@ versions
    - Previously-installed versions are kept locally on the device, unless
    manually deleted, which provides an easy route for roll-backs to undesired
    changes (e.g. during development)
-- Allows updating the [bootstrap image](../development/bootstrap) to match the current version
+- Allows updating the [bootstrap image](@/development/bootstrap/index.md) to match the current version
 - Allows loading remote versions (including from custom docker-hub repositories)
 - Allows manually uploading docker images from the surface computer
 - If an undetected failure somehow occurs in BlueOS (or if a broken version gets