ci: Adopt rust-toolchain instead

Signed-off-by: Xuanwo <github@xuanwo.io>

.github/workflows/deploy_docs.yml

@@ -16,11 +16,6 @@ jobs:
       - name: Install jq
         run: sudo apt-get install -y jq
 
-      - uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          toolchain: 1.56.0
-          override: true
       - uses: actions-rs/cargo@v1
         with:
           command: doc

.github/workflows/release.yml

@@ -10,10 +10,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/toolchain@v1
-        with:
-          toolchain: 1.56.0
-          override: true
       - uses: katyo/publish-crates@v1
         with:
           registry-token: ${{ secrets.CARGO_REGISTRY_TOKEN }}
@@ -37,12 +33,6 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v3
-
-      - uses: actions-rs/toolchain@v1
-        with:
-          toolchain: 1.56.0
-          override: true
-
       - uses: taiki-e/upload-rust-binary-action@v1
         with:
           bin: difft

.github/workflows/test.yml

@@ -8,11 +8,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          toolchain: 1.56.0
-          override: true
       - uses: actions-rs/cargo@v1
         with:
           command: test
@@ -22,11 +17,6 @@ jobs:
     runs-on: macos-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          toolchain: 1.56.0
-          override: true
       - uses: actions-rs/cargo@v1
         with:
           command: test
@@ -36,11 +26,6 @@ jobs:
     runs-on: windows-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          toolchain: 1.56.0
-          override: true
       - uses: actions-rs/cargo@v1
         with:
           command: test
@@ -50,11 +35,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          toolchain: 1.56.0
-          override: true
       - name: Generate output for all sample files
         run: ./sample_files/compare_all.sh
       - name: Verify output is unchanged
@@ -65,11 +45,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          toolchain: 1.56.0
-          override: true
       - uses: actions-rs/cargo@v1
         with:
           command: package
@@ -80,12 +55,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          toolchain: 1.56.0
-          override: true
-      - run: rustup component add rustfmt
       - uses: actions-rs/cargo@v1
         with:
           command: fmt

rust-toolchain.toml

@@ -0,0 +1,3 @@
+[toolchain]
+channel = "1.56"
+components = ["rustfmt"]