test(typeahead-select): Add tests

[yasincaliskan]

• I'm not sure if we can add tests for dropdown-related components. I'm open to your suggestions.

[edizcelik]

I guess we should have tests that checks the following scenarios:

Scenario 1:

• Render TypeaheadSelect with 3 dropdown options. Initially there shouldn't be any selected option and TypeaheadSelect should allow selection of only one option.
• Click/focus on the TypeaheadSelect and see if the dropdown menu is opened.
• Click/focus on the second item in the dropdown menu. See if the dropdown is closed and the selected option is displayed correctly.

Scenario 2:

• Render TypeaheadSelect with 3 dropdown options. Initially there shouldn't be any selected option and TypeaheadSelect should allow selection of only one option.
• Click/focus on the TypeaheadSelect and see if the dropdown menu is opened.
• Type second-dropdown into the input to filter dropdown options. Check if the dropdown option with title second-dropdown-option is visible on the dropdown menu.
• Focus on that item, and then select it. See if the dropdown is closed and the selected option is displayed correctly.

Scenario 3:

• Render TypeaheadSelect with 3 dropdown options. Initially there shouldn't be any selected option and TypeaheadSelect should allow selection of more than one option.
• Click/focus on the TypeaheadSelect and see if the dropdown menu is opened.
• Click/focus on the second item in the dropdown menu. See if the dropdown is still open and the selected option is displayed correctly. See if the second item is not displayed in the dropdown menu anymore.
• Click/focus on another dropdown option. See if the tag for it is added as it should now be selected.