Fix crop tool not saving config when navigating away

Summary:
Tool settings are saved in `toolDeactivated`, which is only triggered
when the tool is exited gracefully (e.g. when clicking Crop or Cancel).
This patch calls `toolDeactivated` when the parent `RasterImageView`
object is destroyed, ensuring settings are saved even when navigating
away, e.g. to another image, or back to {nav Browse}.

BUG: 392036

Test Plan:
{nav Crop} tool > activate/deactivate {nav Advanced} > navigate to next
image > open {nav Crop} tool > ensure the {nav Advanced} state is saved.
Also navigate away by clicking {nav Browse}.
Ensure navigating without {nav Crop} active is unaffected.

Reviewers: #gwenview, rkflx

Reviewed By: #gwenview, rkflx

Differential Revision: https://phabricator.kde.org/D11535