UI: Change default simple audio bitrate to 160

The audio bitrate required is insignificant relative to the video
bitrate, and due to the fact that it's possible that a lower-quality
encoder may be in use (such as FFmpeg's AAC encoder), setting the
default to 160 is really more ideal to reducee any potential quality
loss.

obs/window-basic-main.cpp

@@ -458,7 +458,7 @@ bool OBSBasic::InitBasicConfigDefaults()
 			GetDefaultVideoSavePath().c_str());
 	config_set_default_uint  (basicConfig, "SimpleOutput", "VBitrate",
 			2500);
-	config_set_default_uint  (basicConfig, "SimpleOutput", "ABitrate", 128);
+	config_set_default_uint  (basicConfig, "SimpleOutput", "ABitrate", 160);
 	config_set_default_bool  (basicConfig, "SimpleOutput", "Reconnect",
 			true);
 	config_set_default_uint  (basicConfig, "SimpleOutput", "RetryDelay",