feat(GlListbox): convert header slot to a prop
What does this MR do?
This drops the header slot in favor of a prop. The slot was deemed too flexible. By only allowing a plain string in the header, we ensure that listbox usages don't deviate from the designs too easily.
BREAKING CHANGE: GlListbox usages should be updated to pass the header
via the headerText
prop instead of the header
slot.
Integration
We don't seem to be using the header
slot anywhere in GitLab at the moment, so no integration branch is provided with this MR.
Edited by Paul Gascou-Vaillancourt