feat: add go solution to problem No.1576

Author: yanglbme

solution/1500-1599/1576.Replace All ?'s to Avoid Consecutive Repeating Characters/README.md

@@ -108,9 +108,22 @@ public String modifyString(String s) {
 }
 ```
 
-### **...**
-```
-
+### **Go**
+```go
+func modifyString(s string) string {
+	data := []byte(" " + s + " ")
+	for i, c := range data {
+		if c == byte('?') {
+			ahead, behind := data[i-1], data[i+1]
+			for t := byte('a'); t <= byte('z'); t++ {
+				if t != ahead && t != behind {
+					data[i] = t
+				}
+			}
+		}
+	}
+	return string(data[1 : len(data)-1])
+}
 ```
 
 <!-- tabs:end -->

solution/1500-1599/1576.Replace All ?'s to Avoid Consecutive Repeating Characters/README_EN.md

@@ -103,9 +103,22 @@ public String modifyString(String s) {
 }
 ```
 
-### **...**
-```
-
+### **Go**
+```go
+func modifyString(s string) string {
+	data := []byte(" " + s + " ")
+	for i, c := range data {
+		if c == byte('?') {
+			ahead, behind := data[i-1], data[i+1]
+			for t := byte('a'); t <= byte('z'); t++ {
+				if t != ahead && t != behind {
+					data[i] = t
+				}
+			}
+		}
+	}
+	return string(data[1 : len(data)-1])
+}
 ```
 
 <!-- tabs:end -->