try to fix docker envs

Author: vgvoleg

tests/slo/Dockerfile

@@ -4,5 +4,6 @@ WORKDIR /src
 RUN python -m pip install --upgrade pip && python -m pip install -e . && python -m pip install -r tests/slo/requirements.txt
 WORKDIR tests/slo
 ARG SDK_SERVICE
+ENV SDK_SERVICE=$SDK_SERVICE
 
 ENTRYPOINT ["python", "src"]