Fix column growth issue in Data tables

[jordankoschei-okta]

This PR addresses an issue that @sherizada-okta discovered, in which the resize handle was offset when resizing columns in Data Table:

This issue was present in both the original DataTable implementation and the rebuilt DataView implementation.

Solution

The cells in each row adjust to fit the space allotted to them. The final cell expands to fill the remaining space in the table.

In the body rows, this width is the same, since the structure of each cell is identical across rows.

In the table head, however, the "Actions" column has a different width because it does not include the action buttons present in the body cells of the same column.

To fix this, I borrowed a solution from the drag handle column — in the table head, we now render an invisible set of action buttons to match the row actions in the body. This ensures that the column has the same width.

This PR also fixes a regression in which the resize handle was being disabled by an unrelated CSS change.

[bryancunningham-okta]

One comment. Seems good though! 👍

[KevinGhadyani-Okta]

There's a lot going on in here that I don't really understand doing an async PR review. If we need to do a more thorough review, I can setup a meeting. Otherwise, it looks fine. I assume these changes work.