* Sync parmetis_wrapper with changes in metadata.json
1. In the preprocess.py, make sure that num_partitions is defined as input argument. Also, align 'input_dir' with the input dataset. schema_file is assumed to be located inside the input_dir. Also, graph_stats.txt file is assumed to be present in the input_dir.
2. Use DGL_HOME environment variable so that parmetis_wrapper command can be run anywhere.
* Fix CI test failure cases.
* Addressing CI review comments.
* Addressing CI test failures.
* Applying lintrunner patch
* Creating ParMETIS wrapper script to run parmetis using one script from user perspective
* Addressed all the CI comments from PR https://github.com/dmlc/dgl/pull/4529
* Addressing CI comments.
* Isort, and black changes.
* Replaced python with python3
* Replaced single quote with double quotes per suggestion.
* Removed print statement
* Addressing CI Commets.
* Addressing CI review comments.
* Addressing CI comments as per chime discussion with Rui
* CI Comments, Black and isort changes
* Align with code refactoring, black, isort and code review comments.
* Addressing CI review comments, and fixing merge issues with the master branch
* Updated with proper unit test skip decorator
kylasa