Make test-http(s)-set-timeout-server tests more similar and resolve the
following issues:
* `test-http-set-timeout-server.js` had a `secReceived` check in
`serverResponseTimeoutWithPipeline()` that was added to prevent
flakiness, but this did not exist in the https counterpart.
* `test-https-set-timeout-server.js` utilized `common.mustCall()`,
`common.mustNotCall()`, etc., while the http counterpart utilized the
old method of checking flags on exit of the process.
Refs: https://github.com/nodejs/node/issues/13588
PR-URL: https://github.com/nodejs/node/pull/13625
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Alexey Orlenko <eaglexrlnk@gmail.com>
jklepatch