Middlware: `RequestRecorder` reports calls bellow 1ms as decimal value

[Gabrielopesantos]

Description

RequestRecorder records service RPC calls as a decimal number when when are <1ms. #12813

Testing & Reproduction steps

• Test created

A test has been created, however, I am not sure about the test name and arrange/preparation step. Also, with the changes the value is supposed to have 3 decimal digits, however it is returned as the following example: new_rpc_metrics_2_rpc_server_call{errored="false",leader="true",method="Status.Ping",request_type="read",rpc_type="net/rpc",quantile="0.5"} 0.08299999684095383 Some feedback on these issues would be appreciated.

PR Checklist

• [X] updated test coverage
• [X] external facing docs updated
• [X] not a security concern
• [ ] checklist folder consulted

[hashicorp-cla]

All committers have signed the CLA.

[hashicorp-ci]

🤔 This PR has changes in the website/ directory but does not have a type/docs-cherrypick label. If the changes are for the next version, this can be ignored. If they are updates to current docs, attach the label to auto cherrypick to the stable-website branch after merging.

[Amier3]

Hey @Gabrielopesantos

Thanks for the quick PR! We'll try to get you some feedback on the issue you're having this week

[github-actions[bot]]

This pull request has been automatically flagged for inactivity because it has not been acted upon in the last 60 days. It will be closed if no new activity occurs in the next 30 days. Please feel free to re-open to resurrect the change if you feel this has happened by mistake. Thank you for your contributions.