Merge pull request #133 from ShannonChenCHN/master

Modified the audio resource URL for GNU

README.md

@@ -24,7 +24,7 @@
 | facade [🔊](http://dict.youdao.com/dictvoice?audio=facade&type=1) | ✅ [fə'sɑːd]]| ❌ ['feikeid] |
 | fedora [🔊](http://dict.youdao.com/dictvoice?audio=fedora&type=1) | ✅ [fɪ'dɔːrə]| ❌ ['fedərə] |
 | Git [🔊](http://dict.youdao.com/dictvoice?audio=git&type=1) | ✅ [ɡɪt] | ❌ [dʒɪt; jɪt] |
-| GNU [🔊](http://dict.youdao.com/dictvoice?audio=GNU&type=1) | ✅ [gnu:] | |
+| GNU [🔊](https://upload.wikimedia.org/wikipedia/commons/2/24/En-gnu.ogg) | ✅ [gnu:] | |
 | GUI [🔊](http://dict.youdao.com/dictvoice?audio=GUI&type=1) | ✅ [ˈɡui] | |
 | Haskell [🔊](http://dict.youdao.com/dictvoice?audio=haskell&type=1) | ✅ [ˈhæskəl] | ❌ [hæˈskəl] |
 | height [🔊](http://dict.youdao.com/dictvoice?audio=height&type=1) | ✅ [haɪt] | ❌ [heɪt] |