Replace git.io link in README with IPv6-compatible link.

[kotx]

Git.io doesn't support IPv6. This causes an obscure error on installation of fish:

kot@pom ~> curl -sL https://git.io/fisher | source && fisher install jorgebucaran/fisher
fish: Unknown command: fisher
fish:
curl -sL https://git.io/fisher | source && fisher install jorgebucaran/fisher
                                           ^~~~~^

This is because git.io cannot be resolved:

kot@pom ~ [7]> ping git.io
ping: connect: Network is unreachable

[kotx]

Actually I just replaced the url with https://raw.githubusercontent.com/jorgebucaran/fisher/HEAD/functions/fisher.fish but then GitHub doesn't support IPv6 on some endpoints so Fisher wouldn't work anyway:

kot@pom ~ [1]> curl -sL https://raw.githubusercontent.com/jorgebucaran/fisher/HEAD/functions/fisher.fish | source && fisher install jorgebucaran/fisher
fisher install version 4.4.3
Fetching https://api.github.com/repos/jorgebucaran/fisher/tarball/HEAD
fisher: Invalid plugin name or host unavailable: "jorgebucaran/fisher"

This would require more changes than just to the README.

A workaround for now is to use a NAT64 service.

[jorgebucaran]

How can I reproduce this? (Link works fine for me). Are you using an exotic terminal?

[kotx]

How can I reproduce this? (Link works fine for me). Are you using an exotic terminal?

~ ❱ dig +short git.io AAAA
~ ❱ dig +short git.io A
140.82.113.22

[jorgebucaran]

Who is affected by this? I am able to install Fisher using the instructions in the README.

[igalic]

am increasing number of people who's ISPs only provide IPv6, because IPv4 shortage is real.

[jorgebucaran]

We should be good now 67bec738dbec2442d05d09ef72b2be82acb1d774. Thank you, @igalic and @kotx.