fix typo: MP# -> MP3 (#1120)

README.md

@@ -94,7 +94,7 @@ Please take a quick gander at the [contribution guidelines](https://github.com/a
 * [go_mediainfo](https://github.com/zhulik/go_mediainfo) - libmediainfo bindings for go.
 * [id3v2](https://github.com/bogem/id3v2) - Fast and stable ID3 parsing and writing library for Go
 * [mix](https://github.com/go-mix/mix) - Sequence-based Go-native audio mixer for music apps.
-* [mp3](https://github.com/tcolgate/mp3) - A native Go MP# decoder.
+* [mp3](https://github.com/tcolgate/mp3) - A native Go MP3 decoder.
 * [music-theory](https://github.com/go-music-theory/music-theory) - Music theory models in Go.
 * [PortAudio](https://github.com/gordonklaus/portaudio) - Go bindings for the PortAudio audio I/O library.
 * [portmidi](https://github.com/rakyll/portmidi) - Go bindings for PortMidi.