Allow canceling "Import from File" -> "Existing" operation

[valscion]

I recently went to import a Swagger JSON file and thought I'd want to import that to an existing workspace, i.e. click the "Existing" button in this UI:

However, after clicking that button I came to the conclusion that no, I'd want to cancel this operation and rather import to a new workspace. However, as far as I was able to tell, there is no option to cancel the import process anymore in this UI but one has to quit the entire Insomnia application to cancel the import process:

EDIT: Also it looks like one can't cancel the process even before selecting "New" or "Existing" option as the first modal also can't be closed with a cancel action.