Test for changes to CLI flags

[ethan-readyset]

Description

Cloud relies on the consistency of our CLI flags. There have been instances where we've introduced a breaking change to our CLI flags and broken part of Cloud in the process. To avoid this, we should add a simple integration test that will fail if our CLI flags change or if the values accepted by our CLI flags change.

One way to do this would be to dump a "schema" of our CLI options by serializing the relevant struct definitions and writing it to disk. When this schema is changed, it would force us to deliberately write a new schema file to avoid the test failure. We should also add a comment near the test that reminds the developer making the change to check with the Cloud team to make sure the change doesn't break part of Cloud.

Change in user-visible behavior

No

Requires documentation change

No

[gvsg-rs]

We should, at a minimum, add a test that breaks when CLI flags change.

[jasobrown-rs]

NOTE: this test(s) needs to include env vars, as well.