Filter chooser model now accepts shorthand number inputs

[jskupsik]

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[amcclain]

I was initially concerned that we were going to emit markup somewhere in the stack, given that the rendering pipeline for FilterChooser is fully React (as opposed to the issue handled by #3154 where we pipe into ag-grid context menus that require strings).

But that point is rendered moot 😁 by the use of stripTags below, which is where we first ended up with [object Object] before this fix.

I thought maybe we could update that to let this method return either a stripped string or an element, but we look to do string-based comparisons downstream so, yeah, we def. need this to return a string