github: pin actions/checkout version by hash

.github/workflows/build.yml

@@ -16,7 +16,7 @@ jobs:
         operating-system: [ ubuntu-latest, windows-latest, macos-latest ]
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846
     - name: Install Rust (stable)
       uses: actions-rs/toolchain@v1
       with:
@@ -40,7 +40,7 @@ jobs:
     name: Check formatting
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846
       - uses: actions-rs/toolchain@v1
         with:
           toolchain: nightly
@@ -57,7 +57,7 @@ jobs:
     permissions: write-all
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846
       - uses: actions-rs/toolchain@v1
         with:
           toolchain: stable
@@ -74,7 +74,7 @@ jobs:
     permissions: write-all
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846
       - uses: actions-rs/toolchain@v1
         with:
           toolchain: nightly

.github/workflows/nix-linux.yml

@@ -14,7 +14,7 @@ jobs:
     name: nix-build
     timeout-minutes: 20
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846
         with:
           fetch-depth: 0
       - uses: cachix/install-nix-action@v16

.github/workflows/release.yml

@@ -28,7 +28,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v3
+      uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846
     - name: Install packages (Ubuntu)
       if: matrix.os == 'ubuntu-20.04'
       run: |

.github/workflows/scorecards.yml

@@ -22,7 +22,7 @@ jobs:
 
     steps:
       - name: "Checkout code"
-        uses: actions/checkout@v3 # v2.4.0
+        uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846
         with:
           persist-credentials: false