chore(ci): pin actions to sha for hardening

.github/workflows/rust.yml

@@ -14,13 +14,11 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29  # v4
       - name: Install Rust
-        uses: actions-rs/toolchain@v1
+        uses: dtolnay/rust-toolchain@d388a4836fcdbde0e50e395dc79a2670ccdef13f  # stable
         with:
           toolchain: '1.76.0'
-          profile: minimal
-          override: true
           target: x86_64-unknown-linux-gnu
       - name: Build
         run: cargo build --verbose
@@ -30,23 +28,23 @@ jobs:
   cargo-clippy:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29  # v4
       - name: Run Clippy
         run: cargo clippy --all-targets --all-features
 
   cargo-fmt:
     name: Ensure 'cargo fmt' has been run
     runs-on: ubuntu-20.04
     steps:
-      - uses: dtolnay/rust-toolchain@stable
+      - uses: dtolnay/rust-toolchain@d388a4836fcdbde0e50e395dc79a2670ccdef13f  # stable
         with:
           components: rustfmt
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29  # v4
       - run: cargo fmt -- --check
 
   cargo-audit:
     name: cargo audit
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29  # v4
       - run: cargo audit