docs: add workspaces caveat note
Description
Added note regarding Workspaces using local dependencies if available rather than reaching for the registry. This addition was prompted by a tweet from @arcanis as I believe it is a bit easier to understand relative to the existing mention of this caveat.
Additional note added as a nested list item under the existing mention. I've transcribed the tweet to fit in the context, however I would appreciate any feedback you may have.
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Perhaps this may not be the best way to implement this note due to the spacing below nested list items.