ci: fix no-std check

Author: k-nasa

Diff for: .github/workflows/ci.yml

@@ -86,7 +86,7 @@ jobs:
       uses: actions-rs/cargo@v1
       with:
         command:  check
-        args: --no-default-features --features alloc --target thumbv7m-none-eabi -v
+        args: --no-default-features --features alloc --target thumbv7m-none-eabi -Z avoid-dev-deps
 
   check_fmt_and_docs:
     name: Checking fmt and docs