sh/tests: Cut down builtins/read12.0 by 2 seconds

[jilles]

Summary

Since the test assumes a 250 ms response time, the test delay can be 1
second instead of 3.

[des]

Since the test assumes a 250 ms response time, the test delay can be 1 second instead of 3.

That is a complete non sequitur.

Why does the test need to be shortened?

[jilles]

In D55191#1261862, @des wrote:

Since the test assumes a 250 ms response time, the test delay can be 1 second instead of 3.

That is a complete non sequitur.

Why does the test need to be shortened?

To make it nicer to develop sh(1), I have gone to great lengths to make its tests fast. Avoiding sleeps also improves reliability of the tests.

I am aware that tests for other parts of the system may be unnecessarily slow.