Update README.md

Author: laparca

README.md

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+[![codecov](https://codecov.io/gh/lazy-coders/lzc-coro/graph/badge.svg?token=O1N5INRR9G)](https://codecov.io/gh/lazy-coders/lzc-coro)
+
 # LaZyCoders COROutine library
 
-WIP: at this momento the repository is in maintenance mode.
+WIP: at this momento the repository is in maintenance mode.