[BUG] TaskBoard `columnResize` feature collides with `columnLock`

[willydee]

Description

When both features are enabled on a TaskBoard, and horizontal overflow is triggered, the header of the locked column gets pushed out of place.

Steps to Reproduce

1. Go to https://bryntum.com/products/taskboard/examples/locked-column/
2. Open code editor
3. Add to features section: columnResize : true
4. Collapse/expand some columns
5. Observe the header of the locked column

Expected Behavior

Header of the locked column should always stay in place, lining up with its associated content.

Actual Behavior

Header of the locked column gets pushed to the end or even out of the screen.

Screenshots / Logs

Environment

• Bryntum Version: 6.3.3

Additional Context

Reported for Angular framework, but also reproducible in vanilla JS.