Remove unused files.

Signed-off-by: Jay Zhang <jiz@microsoft.com>

Author: fatcat-z

.github/workflows/keras_unit_test_core.yml

@@ -42,8 +42,6 @@ jobs:
           pip install timeout-decorator
           pip install coloredlogs flatbuffers
           pip install tensorflow==${{ matrix.tf_version }}
-          pip install -r requirements.txt
-          pip install -r requirements-dev.txt
           pip install pytest pytest-cov pytest-runner
           pip install onnxruntime==${{ matrix.ort_version }}