Update header block class on snippets page
What does this MR do?
Changes gray block in Snippets
to new white sub header style
What are the relevant issue numbers?
Closes #19692 (closed)
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Changes gray block in Snippets
to new white sub header style
Closes #19692 (closed)