Update MSRV and remove dependency

[Expyron]

This updates the MSRV to 1.63, which is the minimum version that allows removing the lazy_static dependency.

I understand this is a leap from the current 1.31 MSRV, however:

• 1.63 was released 4 years ago in 2022
• According to the crates.io stats, 99.7% of downloads are from 1.63 or above
• Most of the crates that depend on this one already require 1.63+ (e.g. openssl-sys at 1.80, zstd-sys at 1.64, libz-sys at 1.63, …)
• Users who need older Rust versions can still pin to previous releases of this crate