Broken links in ORC format specifications

In the ORC specification, under section "File Tail", there is a link that is intended to go to the Protobuf definition of ORC files: https://github.com/apache/orc/blob/main/proto/orc_proto.proto . This link leads to a 404, as the actual Protobuf definition has been moved to the orc-format repo here: https://github.com/apache/orc-format/blob/main/src/main/proto/orc/proto/orc_proto.proto .

The fix would be to correct this link in the 3 ORC format specifications, ORC v0, ORC v1, and ORC v2. Furthermore, the new orc-format repo has the wrong link too, again for all three versions of the spec. It should be correct in those 3 files as well.

This is a pretty small issue but it was actually tough for me as a new user to find the original file, since it had gone to a different repo.