[router] Fix twine uploading (sgl-project#3095)

Author: ByronHsu

.github/workflows/release-pypi-router.yml

@@ -84,6 +84,7 @@ jobs:
       - name: Build SDist
         run: |
           pip install build
+          python -m pip install -U packaging
           python -m build --sdist
 
       - uses: actions/upload-artifact@v4

sgl-router/pyproject.toml

@@ -20,6 +20,10 @@ classifiers = [
 [tool.setuptools.packages]
 find = { where = ["py_src"] }
 
+# workaround for https://github.com/pypa/twine/issues/1216
+[tool.setuptools]
+license-files = []
+
 [[tool.setuptools-rust.ext-modules]]
 target = "sglang_router_rs"
 path = "Cargo.toml"