Store all the data that's contained within an `Axis` as flat properties on the view.

This applies to checks and XY views

Can we store all the data that's contained within an `Axis` as flat properties on the view instead? Kinda like the scatter view does. The `Axis` feels like a model that we've dragged with us since the Chronograf 1.x + dygraphs days that ideally wouldn't exist any more.

_Originally posted by @chnn in https://github.com/influxdata/influxdb/pull/14550_

Start by locating the Axis data used by checks and XY views, then compare it with how the scatter view stores equivalent data. Done means the Axis model is no longer needed and its data is represented as flat properties on each affected view.

Written by the indexing model from the issue text.