Update azure-pipeline.yml

Co-authored-by: Jianjie Liu <liujianji3@gmail.com>

azure-pipeline.yml

@@ -48,7 +48,8 @@ steps:
     pip install --upgrade pip 
     pip install setuptools wheel
     pip install artifacts-keyring --pre
-    pip install -r build_requirements.txt 
+    pip install -r requirements.txt 
+    pip install pytest==5.3.5 pytest-cov==2.8.1
   workingDirectory: $(Build.SourcesDirectory)
   displayName: 'Install dependencies'