Replace lazy_static with OnceLock

[tamaroning]

Hello, I am glad to know that bear is being rewritten in Rust and it sounds interesting.
This patch removes uses of lazy_static since it is going to be deprecated (see rust-lang-nursery/lazy-static.rs#214). The std library now supports OnceCell and OnceLock as alternatives.

[rizsotto]

Hey @tamaroning , thanks for this PR. I was not aware of the lazy_static going to be deprecated. Good catch.

I like that idea to not depending another crate for this. But was looking to the LazyLock, which has similar semantic as lazy_static. I do not worry much that the 1.80 version is very recent and might be not wildly recognized yet... What do you think? Could you update the PR to use LazyLock?

[tamaroning]

I did not know about LazyLock since it was added to the standard library very recently.
As you pointed out, LazyLock is preferable to OnceLock because it is closer to the syntax of lazy_static.

[tamaroning]

fixed

[rizsotto]

Thanks @tamaroning , fantastic speed! 😄