(feat): add option to ignore non-installed languages in the healthcheck

[KaspervdHeijden]

Hi! :wave:

Currently, we get a warning message for every language binary that is not installed. This PR adds the options to "ack" these by adding a setting to be able to ignore a non-installed language.

Options to setup:

    {
        health = {
            ignore = {
                'cargo',
                'Go',
                'javac',
                'julia',
                'luarocks',
                'RubyGem',
            },
        },
    }