GitLab

* [Transform] Random Walk Positional Encoding & Laplacian Positional Encoding

* Update python/dgl/transforms/module.py
Co-authored-by: Mufei Li <mufeili1996@gmail.com>

* Update python/dgl/transforms/functional.py
Co-authored-by: Mufei Li <mufeili1996@gmail.com>

* Update python/dgl/transforms/functional.py
Co-authored-by: Mufei Li <mufeili1996@gmail.com>

* Update python/dgl/transforms/functional.py
Co-authored-by: Mufei Li <mufeili1996@gmail.com>

* Update python/dgl/transforms/functional.py
Co-authored-by: Mufei Li <mufeili1996@gmail.com>

* Update python/dgl/transforms/functional.py
Co-authored-by: Mufei Li <mufeili1996@gmail.com>

* Update python/dgl/transforms/functional.py & python/dgl/transforms/module.py

* update python/dgl/transforms/functional.py

* update doc indexing

* update unit test

* support weighted graphs for random_walk_pe

* change reference

* fix linter errors

* fix datatype compatibility with MXNet & TF

* fix device errors

* fix result precision errors

* change tensorflow abs api

* reboost CI
Co-authored-by: Mufei Li <mufeili1996@gmail.com>