ci(all-features): add -D warnings to cargo check-all-features

Author: rami3l

ci/actions-templates/all-features-template.yaml

@@ -39,4 +39,4 @@ jobs: # skip-all
           rustup target install "$TARGET"
       - name: Build every combination
         run: |
-          cargo check-all-features --root-only
+          cargo check-all-features --root-only -- -D warnings