Update Dockerfile to change CMD instruction for x509_updater.py

Author: ivukotic

x509_secrets/Dockerfile

@@ -28,4 +28,5 @@ RUN echo "Timestamp:" `date --utc` | tee /image-build-info.txt
 
 ENV X509_USER_PROXY /tmp/x509up
 
-CMD sh -c "python3 x509_updater.py --voms $VOMS"
+# CMD sh -c "python3 x509_updater.py --voms $VOMS"
+CMD ["python"]