Allow users to turn off intrinsic function suggestions

Whenever I press ctrl-space to see properties I can set for a resource, this is what I see:


This means I must always scroll to see any relevant properties for a resource after pressing ctrl-space.

I can hide these suggestions by turning off `editor.suggest.showValues` for YAML files, but this means that I also lose suggestions for the values of properties. For example, `UpdateReplacePolicy` then no longer suggests `Delete`/`Retain`/`Snapshot`. Instead, I would like to turn off suggestions for intrinsic functions alone.

For reference, this is what I would _like_ to see when I press ctrl-space in this context:


(I achieved that by manually commenting out the `customTags` in the extension on disk, which is only a temporary solution, and probably has other side effects)