cypress: added jsdialog test

[lpranam]

test for fix from 296d48f

Change-Id: I7033cf78a25235863662da6687107b6a539c2232

• Target version: master

Checklist

• I have run make prettier-write and formatted the code.
• All commits have Change-Id
• I have run tests with make check
• I have issued make run and manually verified that everything looks okay
• Documentation (manuals or wiki) has been updated or is not required

[eszkadev]

valid cypress fail:

 1) JSDialog unit test
       JSDialog check data validity options:
     CypressError: Timed out retrying after 10050ms: `cy.select()` failed because this element:

`<select class="jsdialog ui-listbox " id="allow-input" accesskey="A">...</select>`

is being covered by another element:

`<div class="jsdialog-overlay dimmed" id="modal-dialog-cool_alert-overlay">...</div>`

[lpranam]

requires https://gerrit.libreoffice.org/c/core/+/179402 to pass the test.