Test no_std support

Author: madsmtm

.github/workflows/main.yml

@@ -42,6 +42,12 @@ jobs:
         with:
           command: test
           args: --all-features
+      - uses: actions-rs/cargo@v1
+        # --no-default-features only available since 1.51.0
+        if: matrix.rust != '1.45.0'
+        with:
+          command: test
+          args: --no-default-features
 
   WASM:
     runs-on: ubuntu-latest