Add ERC: Splitting and Merging of NFTs

[nitin312]

When opening a pull request to submit a new EIP, please use the suggested template: https://github.com/ethereum/EIPs/blob/master/eip-template.md

We have a GitHub bot that automatically merges some PRs. It will merge yours immediately if certain criteria are met:

• The PR edits only existing draft PRs.
• The build passes.
• Your GitHub username or email address is listed in the 'author' header of all affected PRs, inside .
• If matching on email address, the email address is the one publicly listed on your GitHub profile.

[eip-review-bot]

File ERCS/erc-7891.md

Requires 1 more reviewers from @g11tech, @SamWilsn, @xinbenlv

[github-actions]

The commit 033f0ab (as a parent of c87988a) contains errors.
Please inspect the Run Summary for details.

[nitin312]

Hi @SamWilsn, I noticed that the file was renamed from eip-6312.md to erc-7891.md, and the EIP number was updated. Could you please clarify why this change was made? Is there a specific reason for the update or renaming?
Thanks!

[bomanaps]

Let's start by making sure all the bot flags get addressed. I think most were due to hyperlink-related issues.