Add requests for PyProject.toml (#10916)

Just like we added to the build_requirements.txt we need requests in
pyproject.toml when building release builds with CUDA on (like on
Windows) without IREE docker images.
diff --git a/runtime/pyproject.toml b/runtime/pyproject.toml
index ecb6641..48190b6 100644
--- a/runtime/pyproject.toml
+++ b/runtime/pyproject.toml
@@ -9,5 +9,6 @@
     "packaging",
     "pybind11>=2.8.0",
     "PyYAML",
+    "requests",
 ]
 build-backend = "setuptools.build_meta"