fix: revert fix to icon list item, use splitting instead

[Arukuen]

fixes #3382

• The previous PR on onPaste causes the issue
  • Removing the code fixes current the issue, including other issues such as pasting always do line breaks
  • The issue in the previous PR (pasting multiple line of list only paste a single line of Icon List Item) is more about splitting.
    • This can be fixed by using supports: { splitting: true } instead, which was already done with the previous deprecation fixes
• Testing:
  • Previous Issue: Pasting from other lists now splits. Tested with Google docs list, WordPress List block, or Stackable Icon List block ✅
  • Current Issue: Pasting now puts the cursor at the end of the line ✅
  • Additional Issue: Pasting now does not force a line break ✅

[github-actions]

🤖 Pull request artifacts

file	commit
pr3384-stackable-3384-merge.zip	aff96fc

[github-actions]

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