Fix list index out of range with setuptools_rust 1.7.0

setuptools_rust/build.py", line 470, in get_dylib_ext_path
host_arch = host_platform.rsplit("-", 1)[1]
IndexError: list index out of range

Closes #1141

Author: emanuele-f

server/pypi/build-wheel.py

@@ -583,7 +583,7 @@ def get_python_env_vars(self, env, pypi_env):
 
         # Overrides sysconfig.get_platform and distutils.util.get_platform.
         # TODO: consider replacing this with crossenv.
-        env["_PYTHON_HOST_PLATFORM"] = f"linux_{ABIS[self.abi].uname_machine}"
+        env["_PYTHON_HOST_PLATFORM"] = f"linux-{ABIS[self.abi].uname_machine}"
 
     @contextmanager
     def env_vars(self):