iox-#5 squash me

.github/workflows/rust.yml

@@ -50,6 +50,7 @@ jobs:
       with:
         rust-version: nightly
         components: llvm-tools-preview
+    - uses: actions-rs/grcov@v0.1
     - name: Setup cache
       uses: actions/cache@v2
       with:
@@ -64,7 +65,6 @@ jobs:
       run: |
         sudo apt update
         sudo apt install -y libacl1-dev libncurses5-dev
-        cargo install grcov
     - name: Build
       env:
         RUSTFLAGS: -Cinstrument-coverage