Freeze pyvo

Author: tikk3r

Singularity.lofar_sksp

@@ -52,7 +52,7 @@ From: tikk3r/lofar-grid-hpccloud:lofar_sksp_base
     pip install aplpy
     pip install xmlrunner
     pip install h5py
-    pip install pyvo
+    pip install "pyvo==0.9.3"
     pip install pyregion
     # Packaged required for cluster catalog.
     pip install --upgrade google-api-python-client