This commit refactors "deno_core" to do fewer boundary crossings
from Rust to V8. In other words we are now calling V8 from Rust fewer
times.
This is done by merging 3 distinct callbacks into a single one. Instead
of having "op resolve" callback, "next tick" callback and "macrotask
queue" callback, we now have only "Deno.core.eventLoopTick" callback,
which is responsible for doing the same actions previous 3 callbacks.
On each of the event loop we were doing at least 2 boundary crosses
(timers macrotask queue callback and unhandled promise rejection
callback) and up to 4 crosses if there were op response and next tick
callbacks coming from Node.js compatibility layer. Now this is all done
in a single callback.
Closes https://github.com/denoland/deno/issues/18620
