CI: test with --all-features

Author: messense

.github/workflows/CI.yml

@@ -33,6 +33,10 @@ jobs:
       - uses: actions-rs/cargo@v1
         with:
           command: test
+      - uses: actions-rs/cargo@v1
+        with:
+          command: test
+          args: --all-features
 
   fmt:
     name: Rustfmt