Update smol requirement from 1 to 2

Updates the requirements on [smol](https://github.com/smol-rs/smol) to permit the latest version.
- [Release notes](https://github.com/smol-rs/smol/releases)
- [Changelog](https://github.com/smol-rs/smol/blob/master/CHANGELOG.md)
- [Commits](https://github.com/smol-rs/smol/compare/v1.0.0...v2.0.0)

---
updated-dependencies:
- dependency-name: smol
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/ci.yml

@@ -45,16 +45,11 @@ jobs:
 
   msrv:
     runs-on: ubuntu-latest
-    strategy:
-      matrix:
-        # When updating this, the reminder to update the minimum supported
-        # Rust version in Cargo.toml.
-        rust: ['1.59.0']
     steps:
       - uses: actions/checkout@v4
-      - name: Install Rust
-        run: rustup update ${{ matrix.rust }} && rustup default ${{ matrix.rust }}
-      - run: cargo build
+      - name: Install cargo-hack
+        uses: taiki-e/install-action@cargo-hack
+      - run: cargo hack build --rust-version
 
   clippy:
     runs-on: ubuntu-latest

Cargo.toml

@@ -5,8 +5,8 @@ name = "async-dup"
 # - Create "v1.x.y" git tag
 version = "1.2.4"
 authors = ["Stjepan Glavina <stjepang@gmail.com>"]
-edition = "2018"
-rust-version = "1.59"
+edition = "2021"
+rust-version = "1.60"
 description = "Duplicate an async I/O handle"
 license = "Apache-2.0 OR MIT"
 repository = "https://github.com/smol-rs/async-dup"
@@ -22,4 +22,4 @@ futures-io = "0.3.5"
 
 [dev-dependencies]
 futures = { version = "0.3.5", default-features = false, features = ["std"] }
-smol = "1"
+smol = "2"