client: Fixed a bug where JSON formatted logs would not show the requested and overlapping cores when failing to reserve cores

[mvegter]

Description

There is a difference between the json and non-json logger resulting in the loss of data.

Testing & Reproduction steps

{
  "@level": "warn",
  "@message": "Unable to exclusively reserve the requested cores",
  "@timestamp": "2025-03-26T14:37:04.459938+01:00",
  "cores": {},
  "overlapping_cores": {}
}

versus

{
  "@level": "warn",
  "@message": "Unable to exclusively reserve the requested cores",
  "@timestamp": "2025-03-26T14:39:03.441068+01:00",
  "cores": [
    1,
    2,
    3
  ],
  "overlapping_cores": [
    3
  ]
}

Links

This was originally introduced by !24304

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  within the public repository.

[tgross]

Thanks @mvegter! This looks great once we tweak the changelog a bit.

[mvegter]

Thanks @tgross , for others to reference, the difference is between stdout and json logger : https://github.com/hashicorp/go-hclog/blob/v1.6.3/intlogger.go#L419-L426 versus https://github.com/hashicorp/go-hclog/blob/v1.6.3/intlogger.go#L645 , where the "%v" will result in the call to Set#String() on stdout versus the JSON encoding not being able to fully encode the value of the custom wrapper interface.

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