[cmake,bugfix] Install <dune-module>-config-version.cmake

The name of the file changed in one of the recent patches. This
change is now also reflected in the install directive. Fixes #1426
(cherry picked from commit 3138d121d61e464e0a95c1ad301b839b492c0c3a)

Signed-off-by: Markus Blatt <markus@dr-blatt.de>