Update README.md

Author: maykar

README.md

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+<h1 align="center"> :warning:  THIS IS THE DEV BRANCH!  :warning:</h1>
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+May contain bugs, broken features, and should generally be avoided.</br></br>Master branch is located here:</br> https://github.com/custom-components/sensor.plex_recently_added</h2>
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 # Plex Recently Added Component
 
 Home Assistant component to feed [Upcoming Media Card](https://github.com/custom-cards/upcoming-media-card) with