[#12329] Refactoring of sortable tables - notifications table

[domoberzin]

Part of #12329

Outline of Solution
This PR refactors the notification-table component under the admin pages to utilize the sortable-table component. Implementation details follow previously merged PRs for different components in the same issues, with the change highlighted below.

Addition of Class and Tooltip options to SortableTableCellData

• This is required to maintain the behavior of the original notifications table, where there are tooltips for the columns with dates. This change is likely to allow more flexibility in the use of sortable tables as well, though this is applied on a cell-by-cell basis.

The notification table maintains more or less the same visual appearance and functionality as it did before these changes.

[github-actions]

Hi @domoberzin, thank you for your interest in contributing to TEAMMATES!
However, your PR does not appear to follow our contribution guidelines:

• Title must start with the issue number the PR is fixing in square brackets, e.g. [#<issue-number>]

Please address the above before we proceed to review your PR.