Sortable WP List Table headers are misaligned

[jeremyfelt]

In WP List Table, non sortable table headers have a padding of padding: 8px 10px;. When a column is set to be sortable, the padding for the table header goes to padding: 0px; and padding is added to the anchor instead of padding: 7px 7px 8px;.

This results in a noticeable 3px difference between the two styles. The sortable version ends up being misaligned with the other items in its column. This behavior changed as of the new admin style merge.

The attached patch brings the sortable item back in line with padding: 7px 7px 8px 10px;.

[iammattthomas]

In 26424:

Correct the alignment of sortable list table headers. Fixes #26131, props jeremyfelt.