perf_hooks,http2: add performance.clear()

Add missing clear() method to `perf_hooks.performance` to
remove the entries from the master timeline to prevent
that from being a memory leak.

Backport-PR-URL: https://github.com/nodejs/node/pull/20456
PR-URL: https://github.com/nodejs/node/pull/18046


Reviewed-By: Matteo Collina <matteo.collina@gmail.com>