[auto] Update onnx to 7ee7d0b - enable Werror=sign-compare on linux (#867)
https://github.com/onnx/onnx/commit/7ee7d0b57a4e292e96f0a6a64021dd169b60d09e
diff --git a/third_party/onnx b/third_party/onnx
index e35126b..7ee7d0b 160000
--- a/third_party/onnx
+++ b/third_party/onnx
@@ -1 +1 @@
-Subproject commit e35126bc4b42b80c3b7f4091efb02e2f5d53dcdd
+Subproject commit 7ee7d0b57a4e292e96f0a6a64021dd169b60d09e