[Caffe2] Move more method implementations from tensor.h to tensor.cc (#34811)
Summary:
To speed up compilation time
Pull Request resolved: https://github.com/pytorch/pytorch/pull/34811
Test Plan: CI
Differential Revision: D20476992
Pulled By: malfet
fbshipit-source-id: 922cde93783fbfc04854851d7a05a635d5239792
