Add a note that the `one_for_one` restart strategy is used

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Hi! Thank you for suture, I found it super useful. 🙏

I also went off on a bit of an API and documentation wild goose chase, hoping that other restart strategies were in the library. The big nods to Erlang in the README and blog posts gave me false hope. But, I finally found #2 and #55.

Any chance you could add a big visible note that suture only implements one_for_one and there are no plans for alternative restart strategies? Just to save Future Mes a similar journey…