bug: gateway conformance non-existent path on dag-cbor

[SgtPooki]

gateway conformance:

--- FAIL: TestPathing/GET_DAG-CBOR_returns_404_on_non-existing_link/Status_code (0.00s)
    run.go:53:
        Name: GET DAG-CBOR returns 404 on non-existing link
        Hint:

        Error: Status code is not 404. It is 200

        Expected Request:
        {
          "method": "GET",
          "path": "/ipfs/bafyreibs4utpgbn7uqegmd2goqz4bkyflre2ek2iwv743fhvylwi4zeeim/foo/i-do-not-exist"
        }

        Actual Request:
        GET /ipfs/bafyreibs4utpgbn7uqegmd2goqz4bkyflre2ek2iwv743fhvylwi4zeeim/foo/i-do-not-exist HTTP/1.1
        Host: host.docker.internal:8080
        User-Agent: Go-http-client/1.1
        Accept-Encoding: gzip



        Expected Response:
        {
          "statusCode": 404
        }

        Actual Response:
        HTTP/1.1 200 OK
        Transfer-Encoding: chunked
        Accept-Ranges: bytes
        Cache-Control: public, max-age=29030400, immutable
        Connection: keep-alive
        Content-Type: application/octet-stream
        Date: Sat, 30 Mar 2024 03:10:13 GMT
        Etag: "bafyreibs4utpgbn7uqegmd2goqz4bkyflre2ek2iwv743fhvylwi4zeeim"
        Keep-Alive: timeout=72
        Location: http://undefined.undefined.host.docker.internal:8080/ipfs/bafyreibs4utpgbn7uqegmd2goqz4bkyflre2ek2iwv743fhvylwi4zeeim/foo/i-do-not-exist
        X-Ipfs-Path: http://host.docker.internal:8080/ipfs/bafyreibs4utpgbn7uqegmd2goqz4bkyflre2ek2iwv743fhvylwi4zeeim/foo/i-do-not-exist

helia-http-gateway log:

Note: I requested http://helia-http-gateway.localhost/ipfs/bafyreibs4utpgbn7uqegmd2goqz4bkyflre2ek2iwv743fhvylwi4zeeim/foo/i-do-not-exist in the browser and i'm running verified-fetch from #36

[helia] 2024-03-30T03:10:49.294Z helia-http-gateway:server fetching url "http://helia-http-gateway.localhost/ipfs/bafyreibs4utpgbn7uqegmd2goqz4bkyflre2ek2iwv743fhvylwi4zeeim/foo/i-do-not-exist" with @helia/verified-fetch
[helia] 2024-03-30T03:10:49.294Z helia:verified-fetch fetch http://helia-http-gateway.localhost/ipfs/bafyreibs4utpgbn7uqegmd2goqz4bkyflre2ek2iwv743fhvylwi4zeeim/foo/i-do-not-exist
[helia] 2024-03-30T03:10:49.294Z helia:verified-fetch:get-resolved-accept-header incoming accept header "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8"
[helia] 2024-03-30T03:10:49.294Z helia:verified-fetch:get-resolved-accept-header no explicit IPLD content-type requested, returning incoming accept header text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8
[helia] 2024-03-30T03:10:49.295Z helia:verified-fetch output type application/json
[helia] 2024-03-30T03:10:49.295Z helia:verified-fetch:trace finding handler for cid code "113" and output type "application/json"
[helia] 2024-03-30T03:10:49.295Z helia:verified-fetch:trace calling handler "handleDagCbor"
[helia] 2024-03-30T03:10:49.295Z helia:verified-fetch:trace fetching bafyreibs4utpgbn7uqegmd2goqz4bkyflre2ek2iwv743fhvylwi4zeeim/foo/i-do-not-exist
[helia] 2024-03-30T03:10:49.296Z helia:verified-fetch could not decode DAG-CBOR as JSON-safe, but the client sent "Accept: application/json" Error: CBOR decode error: tag not supported (42)
[helia]     at tokensToObject (file:///Users/sgtpooki/code/work/protocol.ai/ipfs/helia-http-gateway/node_modules/cborg/lib/decode.js:169:11)
[helia]     at tokenToMap (file:///Users/sgtpooki/code/work/protocol.ai/ipfs/helia-http-gateway/node_modules/cborg/lib/decode.js:118:19)
[helia]     at tokensToObject (file:///Users/sgtpooki/code/work/protocol.ai/ipfs/helia-http-gateway/node_modules/cborg/lib/decode.js:161:12)
[helia]     at tokenToMap (file:///Users/sgtpooki/code/work/protocol.ai/ipfs/helia-http-gateway/node_modules/cborg/lib/decode.js:118:19)
[helia]     at tokensToObject (file:///Users/sgtpooki/code/work/protocol.ai/ipfs/helia-http-gateway/node_modules/cborg/lib/decode.js:161:12)
[helia]     at decodeFirst (file:///Users/sgtpooki/code/work/protocol.ai/ipfs/helia-http-gateway/node_modules/cborg/lib/decode.js:186:19)
[helia]     at decode (file:///Users/sgtpooki/code/work/protocol.ai/ipfs/helia-http-gateway/node_modules/cborg/lib/decode.js:202:32)
[helia]     at dagCborToSafeJSON (file:///Users/sgtpooki/code/work/protocol.ai/ipfs/helia-http-gateway/node_modules/@helia/verified-fetch/dist/src/utils/dag-cbor-to-safe-json.js:9:17)
[helia]     at VerifiedFetch.handleDagCbor (file:///Users/sgtpooki/code/work/protocol.ai/ipfs/helia-http-gateway/node_modules/@helia/verified-fetch/dist/src/verified-fetch.js:194:24)
[helia]     at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
[helia] 2024-03-30T03:10:49.296Z helia-http-gateway:server verified-fetch response not ok:  406
[helia] 2024-03-30T03:10:49.296Z helia-http-gateway:server:trace request destroyed for url "http://helia-http-gateway.localhost/ipfs/bafyreibs4utpgbn7uqegmd2goqz4bkyflre2ek2iwv743fhvylwi4zeeim/foo/i-do-not-exist"