Add Container Cypress test for pathExists and showConfirmationModal

[ndricimrr]

Check if there are any present Cypress tests for this already, and if not, add Cypress test for them.

You may check the implementation to find out how it works:
pathExists and showConfirmationModal .

But it shouldn't be more complicated than having the test click on a button attached to the function call, and then checking the correct alert/log result is shown.

Consider adding it for wc-based luigi container tests and luigi compound tests both if possible.

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This issue is part of #3757 epic