test: improve performance of test-crypto-timing-safe-equal-benchmarks
Resetting require.cache() to Object.create(null)
each time rather than
deleting the specific key results in a 10x improvement in running time.
Fixes: https://github.com/nodejs/node/issues/25984 Refs: https://github.com/nodejs/node/issues/26229
Checklist
-
make -j4 test
(UNIX), orvcbuild test
(Windows) passes -
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