Update 12.B in all baselines #536

Description
Under 12.B Test Procedure for Data Table Header Association:

Update the Test Instructions to -

Check that all columnrow and/or rowcolumn headers are data cells are associated programmatically with all data cellsassociated with relevant header(s). [SC 1.3.1]

Which Baseline
To help us address your issue more effectively, please identify which Baseline has the issue:

• All