Document sensu-go loadit tool

[hillaryfraley]

Description

The docs should explain how to use the loadit tool for performance testing.

Pending work on the loadit readme (see https://github.com/sensu/sensu-go/issues/4175)

Category

This is an issue with:

• [ ] errata (error in doc content)
• [ ] new doc (requires a completely new doc)
• [x] update (add missing or refresh existing content)
• [ ] improvement (improve docs content or format)

Affected pages

https://docs.sensu.io/sensu-go/latest/operations/deploy-sensu/hardware-requirements/

Corrections needed

Add information about the loadit tool

See also: https://github.com/sensu/sensu-go/tree/main/cmd/loadit

[hillaryfraley]

Is https://github.com/sensu/sensu-go/tree/main/cmd/loadit different from https://github.com/sensu/sensu-perf?

edit: answer is yes

[hillaryfraley]

Asked about plans to doc loadit in slack: https://sumologic.slack.com/archives/C024XK35Z3Q/p1643998797236589

[hillaryfraley]

Followed up: https://sumologic.slack.com/archives/C024XK35Z3Q/p1645035903801439

[hillaryfraley]

https://sumologic.slack.com/archives/C024XK35Z3Q/p1658792415328859