Flag path-like codes in diagnosticFilters

[TwitchBronBron]

Now that #1060 merged, we should add some diagnostics to flag when the old style diagnosticFilters pattern looks like a file path instead of a code. This might not be 100% accurate (plugins could do some crazy codes if they wanted to), but it should help almost all the time.

This is going to be a challenge for projects that are trying to migrate from v0 to v1 because their diagnostic filters are no longer compatible.

For example:

{
    "diagnosticFilters": [
         "source/vendor/**/*",
    ]
}

Should be flagged because that is very clearly a glob, and those need to now be in the format:

{
    "diagnosticFilters": [{
        "files": [
            "source/vendor/**/*"
        ]
    }]
}

We could probably flag the following:

• if there is a ./ or ../
• if there is a globstar **
• if there is a .bs or .brs or .xml file extension at the end

[TwitchBronBron]

Alternatively, we could add some type of compatibility flag into the bsconfig to help teams migrate. but hopefully when we get closer to a proper v1 release, we won't have many teams hopping between v0 and v1 so often.

something like:
{
"diagnosticFiltersV0Compatibility": true
"diagnosticFilters": [...theOldStyleHere]
}