Fix T79275: Missing redraw for pinned active tool settings panels

In the 3D view sidebar, the active tool settings panel can be pinned to other
categories, and in those other categories it doesn't redraw when the active
tool changes. This commit checks for pinned panels from the "Tool" category
when checking whether to redraw.

Note that the relatively expensive string comparison is only done for
currently visible pinned panels.

Differential Revision: https://developer.blender.org/D9012