Merge topic 'release-8.1.2' into release

64cbd1f1 Increment version to VTK 8.1.2

Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: Ben Boeckel <ben.boeckel@kitware.com>
Merge-request: !4842

CMake/vtkVersion.cmake

 # VTK version number components.
 set(VTK_MAJOR_VERSION 8)
 set(VTK_MINOR_VERSION 1)
-set(VTK_BUILD_VERSION 1)
+set(VTK_BUILD_VERSION 2)