Fix workspace.resolver to 2024 edition

Author: tyranron

.github/workflows/ci.yml

@@ -288,9 +288,6 @@ jobs:
           toolchain: ${{ matrix.toolchain }}
           target: ${{ matrix.target }}
 
-      - name: Switch Cargo workspace to `resolver = "2"`
-        run: sed -i 's/resolver = "1"/resolver = "2"/' Cargo.toml
-
       - run: cargo check --target ${{ matrix.target }} -p ${{ matrix.crate }}
                    ${{ (matrix.crate == 'juniper' && matrix.target == 'wasm32-unknown-unknown')
                     && '--features js'

Cargo.toml

@@ -1,4 +1,5 @@
 [workspace]
+resolver = "3"
 members = [
     "benches",
     "book",