Automatic update of fbcode/onnx to 2891e1459745933f4bba9a8cb3371cf3c9…

…eb1d16

Summary:
Previous import was 034921bd574cc84906b7996c07873454b7dd4135

Included changes:
- **[2891e145](onnx/onnx@2891e145)**: Fix Unique unit test (pytorch#2381) <Scott McKay>
- **[25cf73e5](onnx/onnx@25cf73e5)**: update shapeInference h file link (pytorch#2369) <prcvih>
- **[e3074bc0](onnx/onnx@e3074bc0)**: modify file path (pytorch#2378) <prcvih>
- **[9058d3a4](onnx/onnx@9058d3a4)**: Incrementing version number to 1.6.0 (pytorch#2353) (pytorch#2385) <Kevin Chen>
- **[c963586d](onnx/onnx@c963586d)**: Remove typing packages from test requirements (pytorch#2375) <Aiken Cairncross>

Test Plan: ci

Reviewed By: bddppq

Differential Revision: D17791527

fbshipit-source-id: 3780893adb0344fad8725406a12128c83aff6757