fix: .deb build (#269)

ui/flutter/linux/assets/com.gopeed.Gopeed.desktop

@@ -0,0 +1,14 @@
+[Desktop Entry]
+Name=Gopeed
+GenericName=Download Manager
+GenericName[zh_CN]=下载器
+GenericName[zh_TW]=下載器
+Comment=High speed downloader that supports all platforms.
+Comment[zh_CN]=支持全平台的高速下载器
+Comment[zh_TW]=支持全平臺的高速下載器
+Terminal=false
+Exec=gopeed
+Icon=com.gopeed.Gopeed
+Type=Application
+Categories=Utility;Internet
+Keywords=Bittorrent;Downloader;