Time.now => Time.current in controllers

What does this MR do?

As part of #216527 (closed), we convert more uses of Time.now to Time.current. This time, it's the controllers which we migrate.

Both CE, and EE.

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Part of #216527 (closed)