test: ipfs add with CIDv1 as default

[lidel]

This PR is only for demonstration purposes, to identify all tests that require refactor and eventually close #4143 and ipfs/specs#247

Motivation

Main use case for CIDv1 is ipfs:// URI and subdomain gateways. In both cases we want case-insensitive base32 to avoid issues like ipfs/ipfs-companion#1006.

MVP: default unixfsv1 to CIDv1

Virtually all DAGs used in mentioned contexts are unixfsv1, so we can effectively solve most of issues by ensuring unixfsv1 imports produce CIDv1:

• ipfs add - here
• ipfs files mkdir|write - feat(unixfs): use cidv1 by default #8886
• MFS root - feat(unixfs): use cidv1 by default #8886
• legacy ipfs object new|put|patch (for completeness, otherwise we will see people producing CIDv0) - feat(cmds/object): use CIDv1 by default #8896

Alternative is to switch the defaults in github.com/ipfs/go-ipfs-files

Identified tests to fix

• ? tests failed out of ? in interop
• go-ipfs-api: ?
• sharness (hard to count, it timeouts because CIDv1 can't be found due to apis producing v0) - migration tool in feat(test): migrate CIDv0-v1 tool #8898

[schomatis]

Similar to #8886, leaving sharness CID translation for last.