Inspector should display template part name

[jameskoster]

In the screenshot above I have selected the "Untitled Template Part" block. The name is clearly communicated in the block toolbar and List View, however in the Inspector it is referenced as "Header". In the unlikely event of a template containing multiple headers, this can feel buggy.

Instead the template name name should be displayed, like so:

We may need to adjust the description too, but that can potentially done as a part of #37220.

[jameskoster]

This seems to be fixed.