[Forwardport] Renamed "Add Block Names to Hints" config setting to represent what it actually does

[adrian-martinez-interactiv4]

Original Pull Request

magento#14939
This config name is notoriously misleading as it does not show the block name at all, instead it shows the block class type. Worse still there is a question about this in the Magento2 certification exam which is utterly confusing due to the poor naming of the config setting.

Description

I have updated the label of this config setting to state what it actually does when enabled, displaying the block class type on the hints.

Fixed Issues (if relevant)

n/a

Manual testing scenarios

• Login to admin, view updated configuration label.
• Set config to "Yes", confirm block class types are still being shown on template hints.

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)