Go-JSON Replacement

[mbolt35]

What does this PR change?

• Replaces json-iter library with go-json: https://github.com/goccy/go-json
  • The json-iter library has a show-stopping bug which will degrade performance of the go runtime almost to a full stop. See this issue for details: Marshaling slice of structs with one NaN value in the first struct fails slowly vs. encoding/json, also has huge error message json-iterator/go#603
  • go-json seems to have a more active maintainer

How does this PR impact users? (This is the kind of thing that goes in release notes!)

• Fix for requests which don't receive responses.

How was this PR tested?

• Using several specific benchmarks that repro'd the bug case in json-iter
• All kubecost ETL structure json encode/decode unit tests are passing.

[AjayTripathy]

Were we able to test this on the scale cluster for possible performance regressions?