fix: usr: Improve EDNS yaml processing

Dig was producing invalid YAML when displaying some EDNS options. This has been corrected.

Split UL into LEASE and LEASE-KEY in yaml mode and make broken down duration a YAML comment.

Display KEY-TAG as an array of integers.

Split the display of COOKIE into CLIENT, SERVER and STATUS.

Make the broken down expire duration a YAML comment.

Closes #5014