Request: Documentation for how to upgrade fleetctl

[zhumo]

This request is expected to be doable in ≤1 sprint. It would be valuable even if nothing else ships.

It will be reviewed by the acting PM for the #g-website product group, and then hopefully prioritized, drafted, and implemented.

Goal

User story
As a Fleet admin,
I want to learn how to update my fleetctl command line tool on my local laptop
so that I can take advantage of the latest features.

For help creating a user story, see "Writing a good user story" in the website handbook.

Changes

This issue's estimation includes completing the following:

• UI changes: TODO
• QA complete?

QA

The testing steps outlined below must be verified before the associated PR is merged. See "Quality" in the website handbook for help.

Manual testing steps

1. Step 1
2. Step 2
3. Step 3

In addition to the steps above, ensure changes have been checked at all breakpoints, and a browser compatibility test has been carried out on supported browsers.

Testing notes

[Sampfluger88]

This can be done by adding a note to the fleetctl preview page and to the docs. Instructions for this are the same as install.