Merge pull request #559 from Schniz/schniz/remove-maintainer-callout

docs: remove maintainer callout

Author: supermacro

README.md

@@ -1,6 +1,3 @@
-> Seeking co-maintainers: I don't have much time to maintain this project these days. If someone would like to jump in and become a co-maintainer, it would be appreciated!
-> See https://github.com/supermacro/neverthrow/issues/531
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 # NeverThrow 🙅
 
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