**Motivation**
"Pages in these categories" field is not focused when the cursor is there, while all the other fields in the form are ( see in the gif below ).
{F18371426}
Also, the currently used widget is deprecated and should be replaced.
**Acceptance Criteria:**
[] "Pages in these categories" gets the focus when clicked/tabbed to, the border becomes blue and bold like on the other elements from the fieldset.
[] TagMultiselectWidget is used instead of the OOUI CapsuleMultiselectWidget
Notes:
- This bug is the result of using `OOUI CapsuleMultiselectWidget`. All other fields in the fieldset with the same functionality use `TagMultiselectWidget`.
OOUI people do not advise using `CapsuleMultiselectWidget`. T183299
- There's a problem with `DeepCategory.test.js`, an unresolved ajax request which makes the next test in the queue fail. Refactoring `DeepCategory` to use `TagMultiselectWidget` will also supposedly solve the problem, because it's not present with `TemplateSearch.js`. For reference: https://integration.wikimedia.org/ci/job/quibble-vendor-mysql-php70-docker/5341/consoleFull
Hint: There is functionality for making the pills clickable and red in the hastemplate field, therefor can be used by deepcat field as well.