ftp/curl: Update to 8.6.0

ChangeLog: https://curl.se/changes.html#8_6_0
PR: 276879
Approved by: maintainer
Exp-run bye: antoine
MFH: 2024Q1
Security: 02e33cd1-c655-11ee-8613-08002784c58d

(cherry picked from commit ed937bd9ad8fab202fbbc82fff0964eb7e715086)