Refactoring of JavaScript dialog window

[rudolf101]

Description

The JavaScript dialog window has received a number of improvements:

• Replaced coverage buttons with RadioButton, now you can initially see which mode is selected
• Removed redundant inscription in the timeout selection field
• Replaced the “OK” button with “Generate Tests”
• Removed unnecessary gaps
• Improved the description of the tooltip for coverage buttons

Now the dialog window looks like this:

Fixes #1671

How to test

Manual tests

Various scenarios have been tested. You can find the examples in the folder `/utbot-js/samples' and try to run UTBot.

Self-check list

• I've set the proper labels for my PR (at least, for category and component).
• PR title and description are clear and intelligible.
• I've added enough comments to my code, particularly in hard-to-understand areas.
• The functionality I've repaired, changed or added is covered with automated tests.
• Manual tests have been provided optionally.
• The documentation for the functionality I've been working on is up-to-date.