docs: correct the cargo test command in the contribution guide (#2182)

Co-authored-by: sxyazi <sxyazi@gmail.com>

.github/workflows/test.yml

@@ -30,4 +30,4 @@ jobs:
         run: cargo build --verbose
 
       - name: Test
-        run: cargo test --all --verbose
+        run: cargo test --workspace --verbose

CONTRIBUTING.md

@@ -79,7 +79,7 @@ A brief overview of the project's structure:
 3. Run the tests:
 
    ```sh
-   cargo test
+   cargo test --workspace
    ```
 
 4. Format the code (requires `rustfmt` nightly):