Fix rules for CC_CACHE_DEPENDENCIES_EXTRA_PATH

Author: judu

layouts/shortcodes/content/cached-dependencies.md

@@ -5,7 +5,8 @@
 You can enable dependencies caching by adding the `CC_CACHE_DEPENDENCIES=true` [environment variable](#setting-up-environment-variables-on-clever-cloud) in your application. It's enabled by default only for Haskell and Rust applications.
 
 To add folders to the dependencies cache, use `CC_CACHE_DEPENDENCIES_EXTRA_PATHS`. These paths should comply with the following rules:
-- Be a subdirectory of the `$HOME` directory
+- Be a subdirectory of the `$HOME` directory, but not the whole `$HOME` directory
+- Be a sibling or a child of the whole `$APP_HOME` directory, but not the whole `$APP_HOME` directory
 - Be relative to the application root directory (e.g. `vendor`, `../dependencies`)
 - Be separated by a `:` if you want to add multiple paths (e.g. `CC_CACHE_DEPENDENCIES_EXTRA_PATHS=vendor:../dependencies`)