setting COCKROACH_ARGS="start-single-node --insecure" does not work

**Describe the problem**

Please describe the issue you observed, and any steps we can take to reproduce it:

setting COCKROACH_ARGS="start-single-node --insecure" does not work

**To Reproduce**

What did you do? Describe in your own words.

If possible, provide steps to reproduce the behavior:

Run the following command

`docker run -e COCKROACH_ARGS="start-single-node --insecure" --rm cockroachdb/cockroach-unstable`

**Expected behavior**
A clear and concise description of what you expected to happen.

An insecure single node container is ready to be used. Instead I get this instead.

`ERROR: unknown command "start-single-node --insecure" for "cockroach"`

I have opened a pull request a while back which should fix this issue here #113556

**Additional data / screenshots**
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**Environment:**
- CockroachDB version [e.g. 2.0.x]
- Server OS: [e.g. Linux/Distrib]
- Client app [e.g. `cockroach sql`, JDBC, ...]

**Additional context**
What was the impact?

Add any other context about the problem here.

Jira issue: CRDB-33684