Make sure coverage is on right source files

Author: aviruthen

tox.ini

@@ -28,4 +28,4 @@ commands =
 description = Run unit tests with coverage
 deps = pytest-cov
 commands =
-    pytest test/unit_tests --cov=src --cov-report=term-missing --cov-report=xml:coverage.xml --cov-fail-under=70
+    pytest test/unit_tests --cov=src/sagemaker --cov-report=term-missing --cov-report=xml:coverage.xml --cov-fail-under=70