Docs: host-gateway-ip daemon option IPv4+IPv6

[robmry]

- What I did

Depends on:

• https://github.com/moby/moby/pull/48807

The host-gateway-ip daemon option now accepts two addresses, one IPv4 and one IPv6.

- How I did it

- How to verify it

- Description for the changelog

n/a

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 59.63%. Comparing base (917d2dc) to head (81380b9).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #5607 +/- ## ======================================= Coverage 59.63% 59.63% ======================================= Files 346 346 Lines 29208 29208 ======================================= Hits 17417 17417 Misses 10822 10822 Partials 969 969 ```