test: remove unused `util` imports
This is #4397 backported for LTS.
A number of tests in test/parallel were importing the util module
via require() but not using util for anything. This removes those
require() statements.
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This is #4397 backported for LTS.
A number of tests in test/parallel were importing the util module
via require() but not using util for anything. This removes those
require() statements.