Allow the `register_toolchains` stub to accept keyword args like the real thing

cmake/dependencies_generator.py

diff --git a/cmake/dependencies_generator.py b/cmake/dependencies_generator.py
index b3bc959..2eabe07 100644
--- a/cmake/dependencies_generator.py
+++ b/cmake/dependencies_generator.py
@@ -87,7 +87,7 @@
         }
     )
 
-  def register_toolchains(self, *args):
+  def register_toolchains(self, *args, **kwargs):
     pass
 
   def use_repo(self, *args, **kwargs):