ggplot gallery: dot and bar plots edits

[OskaratOmni]

Reviewer comments:

I’ve never seen this one used at OMNI so more my own thoughts than OMNI best practice.
Let’s make sure there’s a y-axis label that’s greater than the highest dot.

Not sure if feasible, but could there be a label at the bottom of the columns with the average value?

[dgkeyes]

Given that this isn't something OMNI uses and in the interest of time, I'm going to remove this for now. We can deal with it more later if desired.