feat(ci): add rustfmt check to unit-tests workflow

Signed-off-by: Sandro-Alessio Gierens <sandro@gierens.de>

.github/workflows/unit-tests.yml

@@ -53,3 +53,6 @@ jobs:
 
       - name: Run clippy lints
         run: cargo clippy -- -D warnings 
+
+      - name: Run rustfmt checks
+        run: cargo fmt --check