Upgrade fails on IPv6-only network

[nivex]

github.com is not reachable over IPv6 and therefore the automated upgrade will fail.

root@skylab:~# acme.sh --upgrade --debug 2 2>/tmp/err.log
https://github.com/acmesh-official/acme.sh
v2.8.6
[Sun 28 Jun 2020 11:02:51 AM EDT] Already uptodate!
[Sun 28 Jun 2020 11:02:51 AM EDT] Upgrade success!
root@skylab:~# less /tmp/err.log 
root@skylab:~# acme.sh --upgrade
[Sun 28 Jun 2020 11:04:01 AM EDT] Please refer to https://curl.haxx.se/libcurl/c/libcurl-errors.html for error code: 7
[Sun 28 Jun 2020 11:04:01 AM EDT] Please refer to https://curl.haxx.se/libcurl/c/libcurl-errors.html for error code: 7
[Sun 28 Jun 2020 11:04:01 AM EDT] Already uptodate!
[Sun 28 Jun 2020 11:04:01 AM EDT] Upgrade success!
root@skylab:~# acme.sh --upgrade --debug 2 2>/tmp/err.log
...

Debug log: err.log

[PandemiK911]

Hello, Github's unavailability over IPv6 is a very old troll. I tried to setup a mirror repo (on a IPv6-capable URL) but I'm stuck by an hardcoded URL (as described in #3067).

[nivex]

get.acme.sh related issue

[nivex]

GitLab has IPv6 now. Perhaps that would be a good place to move.

[jimmbelll]

acme.sh --register-account fails because api.zerossl.com doesn't have an IPv6 address.

curl fails with error code 7.

acme.zerossl.com does have IPv6, so this seems like a little oversight.