net/krakend-ce: Update 2.12.1 => 2.13.1

Changelogs:

• https://github.com/krakend/krakend-ce/releases/tag/v2.13.0
• https://github.com/krakend/krakend-ce/releases/tag/v2.13.1
• https://github.com/krakend/krakend-ce/compare/v2.12.1...v2.13.0
• https://github.com/krakend/krakend-ce/compare/v2.13.0...v2.13.1

Approved by: db@, yuri@ (Mentors, implicit)