[Feature Request] Configure entries in "Run by Language" list

Not sure whether this has been brought up before, but it would make the "Run by Language" list much cleaner and the actual selection much easier, if one could suppress language entries from being listed.

Why is this an issue?

I have to maintain a large list of custom `code-runner.executorMap` configurations for the the same language type, i.e., `C` execution maps with different, mutual exclusive library bindings. When it's time to run code, I end up scrolling through a list of languages which have no value to me at that point in time, e.g., Java, Haskell, Clojure etc.

Ideally, the list of applicable languages is already filter according to the source file's extension. Note though, that in my case multiple execution maps per language exist.

Thank you very much.