Reactor Core should not initialize SLF4J immediately at startup

[sagebind]

Reactor initializes SLF4J logging to be initialized statically before a program's main method runs due to this static block:

reactor-core/reactor-core/src/main/java/reactor/util/Loggers.java

Lines 55 to 57 in 7259f57

	static {
	resetLoggerFactory();
	}

This is less-than-ideal for us, since one of the first things we do in our main is do some housekeeping and SLF4J logger configuration. But because Reactor creates a logger factory statically and then logs a message to it here:

reactor-core/reactor-core/src/main/java/reactor/util/Loggers.java

Line 176 in 7259f57

loggerFactory.apply(name).debug("Using Slf4j logging framework");

This forces SLF4J to initialize, and our logging implementation of choice (in our case Logback) to initialize before we've had a chance to configure it how we want to from within main. Reactor should not initialize and then immediately use an SLF4J logger statically.

Motivation

It seems unusual for Reactor to attempt to initialize so much statically. I have not yet run into any other library in the past near-decade since we've been using this method of configuring our logger that attempted to log statically. This is the first and only library that I've attempted to use that was not compatible with our method of configuring loggers.

Desired solution

It seems like other classes such as Hooks in my testing also run statically before main and emit logs, so I am not entirely sure what would have to change. But ideally, logging would be initialized lazily, and no logs should be attempted to be emitted until a Reactor class is actually used at normal runtime.

Considered alternatives

We could rewrite our stack to only use default logger paths and classes such that our logger is able to be initialized in the way we want it to before main gets to run, but this could be quite a bit of work to change for us.

Additional context