slh-dsa: fix --no-default-features tests

Author: erdnaxe

.github/workflows/slh-dsa.yml

@@ -30,6 +30,6 @@ jobs:
         with:
           toolchain: ${{ matrix.rust }}
       - run: cargo check --all-features
-      - run: cargo test --no-default-features TODO
+      - run: cargo test --no-default-features
       - run: cargo test
       - run: cargo test --all-features