Wording change to rules-based conditional formatting dialogue, to better improve UX

Change to the the "percent" option in the conditional formatting UI for charts as it is not intuitive that this is referring to the value of the measure, as a percent within the range of all points.

For most users, it might imply instead that this is referencing the format of the numbers that being entered as tolerances

Please see this thread in the forums:

https://community.powerbi.com/t5/Desktop/Rules-for-graph-formatting-not-applied-correctely/m-p/2950941#U2950941

Suggested wording: "% of range" or similar.