workflow: add release build in Rust workflow

Closure recursive declaration issue was only happening in release build
Could have been detected before if release build was done here

Signed-off-by: Nicolas Buffon <nicolas.buffon@orange.com>

.github/workflows/rust.yml

@@ -25,10 +25,14 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - name: Build source
+      - name: Build
         run: |
           cd rust
           cargo build --verbose
+      - name: Release build
+        run: |
+          cd rust
+          cargo build --release --verbose
       - name: Run tests
         run: |
           cd rust