feat(gateway): update gateway api, no multi-range support

[hacdias]

Requires:

• feat(gateway): more explicit IPFSBackend and no multi-range boxo#369
• Removed TestGatewayMultiRange
• Have updated conformance tests running refactor: multi range request considers servers that do not return multi range gateway-conformance#113

[lidel]

Pushed ae6b113 with pinned conformance CI revision to double-check if unreleased 404 tests from ipfs/gateway-conformance#131 and ipfs/gateway-conformance#132 pass against this PR.
(Would be unfortunate if we realize 404s are broken after this PR is merged)

Will check result tomorrow.

[hacdias]

@lidel seem to pass 😄

[lidel]

Slight concern on user data loss caused by CAR root change

Someone probably built things that depend on exporting CAR from gateway and then importing it to Kubo.

By removing the CAR root we introduce a surface for data loss, as exported full DAG is no longer pinned by default on `ipfs dag import.

We should double check if we change default behavior or not, and document what changed:

• see if we keep useful root when we know it: feat(gateway): more explicit IPFSBackend and no multi-range boxo#369 (comment)
• add/update changelog for Kubo 0.23.md and note when CAR responses no longer have a meaningful root explicitly listed in CARv1, but use bogus bafkqaaa as a placeholder (4XX/5XX errors only, or more?)

[hacdias]

@lidel

see if we keep useful root when we know

Please check my comment on that thread.

add/update changelog for Kubo 0.23.md and note when CAR responses no longer have a meaningful root explicitly listed in CARv1, but use bogus bafkqaaa as a placeholder (4XX/5XX errors only, or more?)

I added the information about what to expect.

addressed