[DeprecationWarning] Replacing soon-to-be-deprecated lazyInitCUDA with lazyInitDevice(at::kCUDA)

[drivanov]

This PR resolves multiple warnings:

[W110 03:11:01.976023226 Context.h:353] Warning: lazyInitCUDA is deprecated. Please use lazyInitDevice(at::kCUDA) instead. (function lazyInitCUDA)
[W110 03:11:01.979291350 Context.h:353] Warning: lazyInitCUDA is deprecated. Please use lazyInitDevice(at::kCUDA) instead. (function lazyInitCUDA)
[W110 03:11:01.980258297 Context.h:353] Warning: lazyInitCUDA is deprecated. Please use lazyInitDevice(at::kCUDA) instead. (function lazyInitCUDA)
[W110 03:11:01.983385323 Context.h:353] Warning: lazyInitCUDA is deprecated. Please use lazyInitDevice(at::kCUDA) instead. (function lazyInitCUDA)
[W110 03:11:01.984356630 Context.h:353] Warning: lazyInitCUDA is deprecated. Please use lazyInitDevice(at::kCUDA) instead. (function lazyInitCUDA)

generated by examples/bgnn/run.py test.

Description

Checklist

Please feel free to remove inapplicable items for your PR.

• The PR title starts with [$CATEGORY] (such as [NN], [Model], [Doc], [Feature]])
• I've leverage the tools to beautify the python and c++ code.
• The PR is complete and small, read the Google eng practice (CL equals to PR) to understand more about small PR. In DGL, we consider PRs with less than 200 lines of core code change are small (example, test and documentation could be exempted).
• To the best of my knowledge, examples are either not affected by this change, or have been fixed to be compatible with this change

Changes

[chang-l]

LGTM

[chang-l]

It passed our CI. Can we merge this @Rhett-Ying ?