Fix
* fix(paraview): remove unnecessary check for import
It is okay to check the servermanager import at the time of instantiating the Helper class, and we
do not need to check for the servermanager when the module is imported.
Signed-off-by: Patrick Avery <patrick.averykitware.com> ([`301b684`](https://github.com/Kitware/trame-vtk/commit/301b684378f30d46e93939da67ebd11f2027bf41))