sharness: use deterministic fixtures during gateway testing

[laurentsenta]

Checklist

• My issue is specific & actionable.
• I am not suggesting a protocol enhancement.
• I have searched on the issue tracker for my issue.

Description

This request was raised by @lidel in ipfs/gateway-conformance#2 (comment)

We are now asking IPIPs writers to provide static fixtures (CARs) files which means it's possible to create deterministic test suites, and we don't need to exercise unrelated parts of the codebase during the test (ipfs add, etc). We plan on using this approach in the gateway conformance testing work.

To validate this approach and make the transition smoother, we will upgrade the current sharness tests to use static test fixtures.

Outcomes:

• Every gateway-related test relies on static car files and ipfs dag import instead of generating data at runtime
• Every gateway-related test relies on deterministic ipns fixtures as well

I'll take some time to look into #7804 at the same time.

[laurentsenta]

note: static ipns fixtures might relates to ipfs/specs#369 and the IPFS_NS_MAP (for DNS link)

[laurentsenta]

PR for static ipns fixtures is implemented in: #9667

Issues:

• ipfs routing put /ipns/key ./record.ipns && ipfs routing get /ipns/key
  • expected: put(K, V) then get(K) should succeed or fail during PUT
  • the GET fails with a "not found"
• ipfs routing put --allow-offline is not implemented
  • Proposal:
    • kubo: https://github.com/ipfs/kubo/compare/feat/offline-put?expand=1
    • interface: https://github.com/ipfs/interface-go-ipfs-core/compare/feat/offline-put?expand=1

Note:

• ipfs routing put /ipns/KEY ./record.ipns prints the SELF key, even though the record might contain a different key. It should print the key that was publish to the routing system (KEY)