Re-consider jemalloc 5?

Currently Fullstaq Ruby is being compiled only against jemalloc 3 and docs state following in README [here](https://github.com/fullstaq-ruby/server-edition/blob/7ff94fde818ecea413d425412984529d5f07e209/README.md#vs-ld_preloading-jemalloc-yourself):

> Only Jemalloc 3 yields reduced memory usage, Jemalloc 5 does not.

However, there are evidences that jemalloc 5 with changed settings can have the almost same behavior as jemalloc 3, e.g. see here: https://twitter.com/wgjordan/status/1440574986264006659

> Jemalloc 5 has time-based purging, the default (10sec) favors perf over memory usage. Set `dirty_decay_ms:0,muzzy_decay_ms:0` for 3.6-like behavior, I found `dirty_decay_ms:1000,muzzy_decay_ms:0` a good balanced tradeoff. I ran jemalloc 5.1 + Ruby 2.5 since 2018.

**Describe the solution you'd like**
So maybe it is time to give jemalloc 5 one more try?

**Additional context**
Some additional discussion can be seen here (however it is not public): https://railsperf.slack.com/archives/C0QKHT5LP/p1651118694838959