CI: Check for expected error

Author: str4d

.github/workflows/_build_and_test.yml

@@ -23,4 +23,8 @@ jobs:
     - name: Build examples
       run: cargo +nightly build --examples --release --verbose
     - name: Run tests
-      run: cargo +nightly test --release --verbose
+      run: |
+        cargo +nightly test --release --verbose 2>&1 | tee stderr.txt
+    - name: Check that tests failed for the expected reason
+      run: |
+        cat stderr.txt | grep -q "Error: unable to find Flipper Zero"