cluster: remove unused backlog argument
Checklist
-
make -j8 test
(UNIX), orvcbuild test nosign
(Windows) passes -
commit message follows commit guidelines
Affected core subsystem(s)
- cluster
Description of change
Removes an unused backlog argument.
CI: https://ci.nodejs.org/job/node-test-pull-request/4345/
EDIT: CI is green except for a flaky test.