Add --workspace to clippy (#3014)

* [DNM] Debug clippy

* add --workspace

Author: alvicsam

cumulus/scripts/ci/gitlab/pipeline/test.yml

@@ -104,4 +104,6 @@ cargo-clippy:
     - .docker-env
     - .common-refs
   script:
-    - SKIP_WASM_BUILD=1 env -u RUSTFLAGS cargo clippy --locked --all-targets
+    - echo $RUSTFLAGS
+    - cargo version && cargo clippy --version
+    - SKIP_WASM_BUILD=1 env -u RUSTFLAGS cargo clippy --locked --all-targets --workspace