Add checkpointing tests

[ankitgola005]

Before submitting

• [ ] Was this discussed/agreed via a Github issue? (no need for typos and docs improvements)
• [ ] Did you read the contributor guideline, Pull Request section?
• [ ] Did you make sure to update the docs?
• [ ] Did you write any new necessary tests?

What does this PR do?

Fixes # (issue).

PR review

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[ankitgola005]

Manual testing results. Note: To be rebased over #251.

Category	pytorch-lightning | pypi		pytorch-lightning | source		lightning | pypi		lightning | source
	G1	G2	G1	G2	G1	G2	G1	G2
HPU General tests	P	P	P	P	P	P	P	P
HPU torch compile tests	P	P	P	P	P	P	P	P
HPU FSDP tests	P	P	P	P	P	P	P	P
HPU Deepspeed tests	P	P	P	P	P	P	P	P
HPU precision test	P	P	P	P	P	P	P	P
Standalone-only single card tests	P	P	P	P	P	P	P	P
Multi card(2) HPU test	P	P	P	P	P	P	P	P
FSDP PT Multi card(2) HPU test	P	P	P	P	P	P	P	P
FSDP Fabric Multi card(2) HPU test	P	P	P	P	P	P	P	P
Testing HPU examples	P	P	P	P	P	P	P	P

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.