chore: remove libipld usage from bitswap module

[hanabi1224]

Summary of changes

(Part of #5014)
libipld crate has been superseded by ipld-core. Also, to upgrade fvmto latest(together with cid version bump), we have to deprecate libipld in which cid will no longer be upgraded. This PR removes libipld usage from bitswap module in preparation for fvm(and cid) upgrade.

Changes introduced in this pull request:

• remove libipld usage from bitswap module

Reference issue to close (if applicable)

Closes

Other information and links

Change checklist

• I have performed a self-review of my own code,
• I have made corresponding changes to the documentation. All new code adheres to the team's documentation standards,
• 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.

[ruseinov]

looks good!