When rescaling DotPlot, mark it as a user action
When rescaling DotPlot, mark it as a user action

We currently skip adding all non-user-initiated rescaling of the axes to
the undo history, and explicitly mark user-initiated resaclings.

This commit, f153e27e4, forgot about the DotPlot, however.

[#97054304] 

concord-consortium/codap,concord-consortium/codap,concord-consortium/codap,concord-consortium/codap,concord-consortium/codap