A function for ending querying in plots

**Is your feature request related to a problem? Please describe.**
I would like to make use of querying in plots so that a user could highlight a region of the plot and then use a keyboard shortcut or press a button to make some action occur (e.g. hide the plotted data within that region). However, at the moment the highlighted region would be left in place unless the user manually stopped the querying. Disabling querying via `configure_item` does not remove the highlighted region that is drawn on the plot.

**Describe the solution you'd like**
The ability to programmatically end querying in plots would solve the issue described in the last part of the previous section. Such a function would also complement the existing `is_plot_queried` and `get_plot_query_area` functions.

**Describe alternatives you've considered**
A modal window created specifically for the purpose could be used and then closed once the action has been performed. However, it does mean adding more steps for the user to perform the action.

**Additional context**
See #1583 for the initial discussion.