PCH Smart Linking: Undo doesn't work for All Blocks option

[acicovic]

Describe the bug

When Smart Linking is applied to all blocks, the undo key shortcut doesn't work. Pressing it doesn't seem to do anything.

To Reproduce

Apply Smart linking to all blocks in an article, and then try to undo the update with Cmd/Ctrl+z

Expected behavior

Links should be removed, but instead they remain.

[vaurdan]

Closed by #2315