Remove suggestion from Going Further

We already generate a BOM entry for each installed gem.  No need
to suggest this as future work.

Signed-off-by: Aidan Delaney <[email protected]>

Author: AidanDelaney

content/docs/buildpack-author-guide/create-buildpack/adding-bill-of-materials.md

@@ -268,7 +268,6 @@ Congratulations! You’ve created your first configurable Cloud Native Buildpack
 Now that you've finished your buildpack, how about extending it? Try:
 
 - Caching the downloaded Ruby version
-- Updating the BOM with all the gems provided by bundler
 - [Packaging your buildpack for distribution][package-a-buildpack]
 
 [package-a-buildpack]: /docs/buildpack-author-guide/package-a-buildpack/