Update Go-CheatSheet.md

Awesome-CheatSheet/ProgrammingLanguage/Go/Go-CheatSheet.md

@@ -7,6 +7,13 @@ var c, python, java bool
 // 声明不同类型的变量，并且赋值
 var i bool, j int = true, 2
 
+// 复杂变量声明
+var (
+	ToBe   bool       = false
+	MaxInt uint64     = 1<<64 - 1
+	z      complex128 = cmplx.Sqrt(-5 + 12i)
+)
+
 // 短声明变量
 c, python, java := true, false, "no!"
 ```