ftp/curl: Backport fixes for unit tests and alt-svc

Backport upstream patches 7e0eea7d7b34b81ca02ffb995ebea22c02cb92d2 and
fbdb1e1dbe824a72f41a104fa26e555cb0b6b45a to fix unit tests with ipfs and
alt-svc mode

References:
https://github.com/curl/curl/commit/7e0eea7d7b34b81ca02ffb995ebea22c02cb92d2
https://github.com/curl/curl/commit/fbdb1e1dbe824a72f41a104fa26e555cb0b6b45a

PR: 286233
Approved by: maintainer timeout, 2+ weeks (including separate mail)