CMake 3.18.6

Source/CMakeVersion.cmake

 # CMake version number components.
 set(CMake_VERSION_MAJOR 3)
 set(CMake_VERSION_MINOR 18)
-set(CMake_VERSION_PATCH 5)
+set(CMake_VERSION_PATCH 6)
 #set(CMake_VERSION_RC 0)
 set(CMake_VERSION_IS_DIRTY 0)