Remove the limitation of try_lock being a protected function.

[RadiantUwU]

This honestly looks like it was completely arbitrary to be limited to pub(crate) even though it didnt need to be like this.

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[jhpratt]

In the tracking issue (#121440), fallible locking is listed as an unresolved question due to the apparent lack of a use case. I am closing this PR for that reason; feel free to start a discussion in that issue regarding your use case if you have one.

[RadiantUwU]

In the tracking issue (#121440), fallible locking is listed as an unresolved question due to the apparent lack of a use case. I am closing this PR for that reason; feel free to start a discussion in that issue regarding your use case if you have one.

I'm trying to implement a ReentrantRwLock and this heavily depends on it.
I had to code my own ReentrantLock (mutex, whatever) for this instead as the stdlib cannot provide what i request.
https://github.com/godotengine/godot/pull/91682/files (This is how it looks in c++, i am currently making it in Rust as well)

The rust implementation of this requires a ReentrantLock that can try_lock.

[RadiantUwU]

I would be more than happy to add a ReentrantRwLock to the std lib directly and make a pull request for it.

[RadiantUwU]

I also failed to mention how Mutex and RwLock both have try_lock, while the ReentrantLock does not.

[jhpratt]

As I said, bring it up in the tracking issue. The relevant people aren't seeing your comments here.