Bump MSRV to 1.85

[taiki-e]

  error: package `async-lock v3.4.2` cannot be built because it requires rustc 1.85 or newer, while the currently active rustc version is 1.71.1

[reneleonhardt]

Readme shows 1.71.
Now that MSRV reached 1.85, are there plans to bump the edition, or to publish a new release since 2024?

[xtqqczze]

It's kind of unnecessary to bump MSRV from 1.71 when you can just do:

cargo update -p async-lock --precise 3.4.1
cargo update -p async-signal@0.2 --precise 0.2.13

If we keep the minimal versions of dependencies updated this would make things easy: #385

[taiki-e]

It's kind of unnecessary to bump MSRV from 1.71 when you can just do:

cargo update -p async-lock --precise 3.4.1
cargo update -p async-signal@0.2 --precise 0.2.13

If we keep the minimal versions of dependencies updated this would make things easy: #385

See the previous discussion in smol-rs/async-io#93 (comment).