chore: fix readme syntax

Author: lukasbach

README.md

@@ -22,7 +22,7 @@ Check the [v2 release notes](https://rct.lukasbach.com/docs/changelog/#200---120
 
 The development of react-complex-tree is supported by the community. Special thanks to:
 
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@@ -35,7 +35,7 @@ The development of react-complex-tree is supported by the community. Special tha
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 Find out [how to support the development of react-complex-tree](https://github.com/sponsors/lukasbach).