Unify context menu opening code (specifically, shift should not open it)

[naterush]

Context menu ignore when shift is pressed code is duplicated in a few places. I think we should move this into the Mito component and stop propagation in the onContextMenu if e.shiftKey. Then we can remove this duplicated code in other places

Originally posted by @marthacryan in https://github.com/mito-ds/mito/pull/1109#pullrequestreview-1802839336