ubuntu22.04应用添加icon

例子应用：
/usr/share/applications/gitkraken.desktop

该文件内容如下：

[Desktop Entry]
Name=gitkraken
Comment=gitkraken
GenericName=Text Editor
Exec=/app/GitKraken-v7.5.5/gitkraken/gitkraken  %F
Icon=/app/GitKraken-v7.5.5/gitkraken/gitkraken.png
Type=Application
StartupNotify=false
StartupWMClass=
Categories=TextEditor;Development;IDE;
MimeType=text/plain;inode/directory;application/x-code-workspace;
Keywords=gitkraken;