Backport of api/monitor: Adding log format to monitor command and debug into release/1.10.x

[hc-github-team-secure-vault-core]

Backport

This PR is auto-generated from #15536 to be assessed for backporting due to the inclusion of the label backport/1.10.x.

WARNING automatic cherry-pick of commits failed. Commits will require human attention.

merge conflict error: POST https://api.github.com/repos/hashicorp/vault/merges: 409 Merge conflict []

The below text is copied from the body of the original PR.

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Adding log_format flag to monitor endpoint as well as debug command. This will allow the option for vault logs being emitted via monitor to come through as JSON format. The default behavior is to emit in the standard log format.

Usage:
vault monitor -log-level=DEBUG -log-format=JSON

curl -H "X-Vault-Request: true" -H "X-Vault-Token: $(vault print token)" http://127.0.0.1:8200/v1/sys/monitor?log_format=json&log_level=trace

vault debug -target=log -log-format=json

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Overview of commits

• 6ee3fcb

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