Refactor benchmark and add no-var eslint rule
This removes all the remaining var
in benchmark
and adds a rule for no-var
in benchmark/.eslintrc.yaml
as proposed in https://github.com/nodejs/node/pull/31592#issuecomment-581189810.
Checklist
-
make -j4 test
(UNIX), orvcbuild test
(Windows) passes -
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