[27.x backport] cli/formatter: bracket IPv6 addrs prepended to ports

[vvoland]

• backport: cli/formatter: bracket IPv6 addrs prepended to ports #5363

- What I did

On docker ps, port bindings with an IPv6 HostIP should have their addresses put into brackets when joining them to their ports.

RFC 3986 (Section 3.2.2) stipulates that IPv6 addresses should be enclosed within square brackets. This RFC is only about URIs. However, doing so here helps user identifier what's part of the IP address and what's the port. It also makes it easier to copy/paste that '[addr]:port' into other software (including browsers).

- How to verify it

CI, or run the following commands with a recent Engine:

$ docker run --rm -d --name c0 -p 8000:80/tcp 5201/udp alpine top
$ docker ps

- Description for the changelog

- IPv6 addresses shown by `docker ps` in port bindings are now bracketed

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 60.98%. Comparing base (a58af37) to head (6ceb0ab).
Report is 5 commits behind head on 27.x.

Additional details and impacted files

@@           Coverage Diff           @@
##             27.x    #5365   +/-   ##
=======================================
  Coverage   60.97%   60.98%           
=======================================
  Files         304      304           
  Lines       21358    21359    +1     
=======================================
+ Hits        13024    13025    +1     
  Misses       7404     7404           
  Partials      930      930