Description

When I read catalog example, I found unnecessary artificial delay Now.
It is because #12896 Merged. So, I remove the line.

Related Issues

• delay taking screenshot to allow GPU thread to render the frame #12896 delay taking screenshot to allow GPU thread to render the frame

Tests

no addition.
test task code is https://github.com/flutter/flutter/blob/master/dev/devicelab/lib/tasks/sample_catalog_generator.dart#L30-L37

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