Add formatting options to the block toolbar for multiple list items

[bph]

What problem does this address?

I copy/pasted a series of list items to the block editor and it retained the bolding of the original. I trie to highlight all list items, to remove the bold formatting.

What is your proposed solution?

Add a formatting choice to the toolbar when multiple list items are highlighted. It would also help with formatting list items in bulk instead of one at a time.

[ellatrix]

Duplicate of #27221