Point to project.toml in docs

lib/kamal/configuration/docs/builder.yml

@@ -8,7 +8,6 @@
 #
 # Options go under the builder key in the root configuration.
 builder:
-
   # Arch
   #
   # The architectures to build for — you can set an array or just a single value.
@@ -34,11 +33,15 @@ builder:
   # Buildpack configuration
   #
   # The build configuration for using pack to build a Cloud Native Buildpack image.
+  #
+  # For additional buildpack customization options you can create a project descriptor
+  # file(project.toml) that the Pack CLI will automatically use.
+  # See https://buildpacks.io/docs/for-app-developers/how-to/build-inputs/use-project-toml/ for more information.
   pack:
     builder: heroku/builder:24
     buildpacks:
-    - heroku/ruby
-    - heroku/procfile
+      - heroku/ruby
+      - heroku/procfile
 
   # Builder cache
   #