Remove finalize from TrueTypeFont

The usage of finalize is discouraged so that it is a good idea to remove it.

I've found a way to do so for org.apache.fontbox.ttf.TrueTypeFont.

All the data of a RandomAccessReadDataStream is copied to a final byte array. The additional RandomAccessReadBuffer isn't needed at all, so that it is save to do nothing when closing a RandomAccessReadDataStream. Now it is save to remove the finalize override from TrueTypeFont