Merge topic 'ot121'

d9bbc2c4 Filters/OpenTURNS: OPENTURNS_USE_FILE was removed

Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: buildbot <buildbot@kitware.com>
Reviewed-by: Ben Boeckel <ben.boeckel@kitware.com>
Merge-request: !10304

Filters/OpenTURNS/CMakeLists.txt

 find_package(OpenTURNS 1.8 REQUIRED)
-# XXX(fixme)
-include(${OPENTURNS_USE_FILE})
+
+if (EXISTS "${OPENTURNS_USE_FILE}")
+  # removed in 1.21
+  include (${OPENTURNS_USE_FILE})
+endif ()
 
 set(classes
   vtkOTDensityMap