run_csis_servers: Update usage and add docs entry

[wpiet]

Amends the usage of the script and the example that show when executed incorrectly.
Adds basic information to the examples section of the documentation.

[wpiet]

Hi,

I ran the invoke project.lint and it produced warnings about unused imports in the file I had changed. So I tried removing them, but after I force-pushed, the avatar check started failing.

Then, I run black and it amended the print function I had changed. Hopefully all checks pass now.

[zxzxwu]

Hi,

I ran the invoke project.lint and it produced warnings about unused imports in the file I had changed. So I tried removing them, but after I force-pushed, the avatar check started failing.

Then, I run black and it amended the print function I had changed. Hopefully all checks pass now.

Failure in Avatar should be an unrelated issue. I am asking Avatar folks to check now.