Fix/636 Pre Classification Popup terms limit removed

[faisal-alvi]

Description of the Change

• This PR removes the maximum allowed term limit (i.e. 100) in the pre-classification popup.
• Instead of fetching all the terms on the new term insertion, it just updates the existing term object by adding a new term item to it. This is super helpful in terms of performance. This change was required because after adding a new term, we need to fetch all the terms for the updated term object, but fetching all the terms is not possible (i.e. { per_page: -1 } does not work).

Closes #636

How to test the Change

Make sure the following issues are fixed.

• The terms beyond 100 are not visible in the pop-up.
• The terms beyond 100 will not be suggested in the drop downs.
• Even if the term is already added, it attempts to re-add because it doesn't detect it within 100 terms.
• When trying to add new terms, it doesn't display the newly added term, even though the term is added to the site.

Also, test the popup; confirm everything related to the popup works.

Changelog Entry

Fixed - Pre Classification Popup Limits to 100 terms

Credits

Props @faisal-alvi @dkotter

Checklist:

• I agree to follow this project's Code of Conduct.
• I have updated the documentation accordingly.
• I have added tests to cover my change.
• All new and existing tests pass.