Replace `Validate` checks from `commons-lang` with `Preconditions` checks from Guava

[TheBusyBiscuit]

See #3585 for context.

In MC 1.19 Spigot has removed commons-lang from its dependencies. We really shouldn't be shading this library just for this one feature and instead switch to what Spigot uses.

So any Validate.notNull(x, msg) will become Preconditions.checkNotNull(x, msg) and any Validate.isTrue(x, msg) shall become Preconditions.checkArgument(x, msg). It would be really helpful if somebody could make a pull request for this and remove commons-lang from our pom.xml.

[Haarolean]

It seems like it's blocked by https://github.com/baked-libs/dough/pull/184 via https://github.com/Slimefun/Slimefun4/pull/3589