ci: add timeout and single-threaded test execution to prevent hangs

Author: nwiizo

.github/workflows/ci.yml

@@ -45,7 +45,8 @@ jobs:
       run: cargo build --verbose
 
     - name: Run tests
-      run: cargo test --verbose
+      timeout-minutes: 10
+      run: cargo test --workspace -- --test-threads=1
 
   cross-platform:
     name: Cross-platform Build