Summary

The documentation for the bl_deleted column says that it is a boolean and should be updated to say it has three values with different meanings

Background

• T414184: Update bl_deleted to support a third state which only hides the block describes the overall task
  • In summary we need to make bl_deleted represent three states (i.e. not deleted, just the block is deleted, and target and block is hidden)
• The documentation for bl_deleted both in code and on mediawiki.org indicates that the field is a boolean
  • We should update this to indicate the different values and their states

Acceptance criteria

• The documentation for bl_deleted indicates this new value and it's meaning