Full Scale Portal Gun [Remix] repaired STL file

This is a replacement for "Portal_Gun_White_Left_Shell_Slice_6.stl" in thing #26027.
The original file specified a triangle count of 6964 triangles, but reached end of file after 6963, so was an invalid STL format. Some tools would refuse to read it; others would read it, but you'd have a hole or perhaps a corrupted final triangle.
This is identical to the original file, but with the missing triangle added to the end.