Merge topic 'update-to-v1.6.0-rc2'

1cf9ebd5

 1.6.0-rc2 is our Nth official release of VTK-m.
Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: Ben Boeckel <ben.boeckel@kitware.com>
Merge-request: !2497

version.txt

-1.6.0-rc1
+1.6.0-rc2