fix: align with Lotus json format for ActorState

[lemmih]

Summary of changes

Changes introduced in this pull request:

• Revert name change in ActorState. I'm not sure if Lotus used Address in the past or if the previous fix was incorrect.

Reference issue to close (if applicable)

Closes #4433

Other information and links

Change checklist

• I have performed a self-review of my own code,
• I have made corresponding changes to the documentation,
• I have added tests that prove my fix is effective or that my feature works (if possible),
• I have made sure the CHANGELOG is up-to-date. All user-facing changes should be reflected in this document.

[lemmih]

@sudo-shashank You renamed the field here: #4392. Do you remember why?

[lemmih]

Mystery solved. FIP0048 renamed the field: https://github.com/filecoin-project/FIPs/blob/master/FIPS/fip-0048.md#new-lookup_delegated_address-syscall-and-state-changes