Removed duplicated points are still included metadata

[cry-inc]

When converting a LAZ file with lots of duplicated points the final point count in the metadata.json file is wrong.
In my case I had an example with 199473004 input points, but a lot of them were filtered out and the actual octree contains only 167678572 points due to many duplicates. This was indicated by lots of warnings like this:

WARN(indexer.cpp:1084): Too many duplicate points were encountered. #points: 1734697, #unique points: 1

This big difference looks dangerous on first glance, but is probably only an inconvenience because not a lot of things rely on the exact point count in that file (especially not the viewer).