pin cache action

Author: Swatinem

.github/workflows/ci.yaml

@@ -51,7 +51,7 @@ jobs:
         components: rustfmt, rust-src
 
     - name: Cache Dependencies
-      uses: Swatinem/rust-cache@v1
+      uses: Swatinem/rust-cache@ce325b60658c1b38465c06cc965b79baf32c1e72
 
     - name: Compile
       run: cargo test --no-run --locked
@@ -82,7 +82,7 @@ jobs:
       run: rustup target add ${{ env.targets }}
 
     - name: Cache Dependencies
-      uses: Swatinem/rust-cache@v1
+      uses: Swatinem/rust-cache@ce325b60658c1b38465c06cc965b79baf32c1e72
 
     - name: Check
       run: |