Download file on build and add _test-unicode-conformance feature

Author: MDLC01

.github/workflows/ci.yml

@@ -8,4 +8,4 @@ jobs:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@stable
       - run: cargo build
-      - run: cargo test
+      - run: cargo test --features=_test-unicode-conformance