feat:对stringkit进行方法的补充，增加相应的单测

src/main/java/com/fanruan/api/util/StringKit.java

@@ -85,5 +85,14 @@ public class StringKit {
     public static boolean isNotBlank(String text) {
         return StringUtils.isNotBlank(text);
     }
+    /**
+     * 对字符串做trim操作
+     *
+     * @param string 源字符串
+     * @return 返回操作后的字符串
+     */
+    public static String trim(String string) {
+        return StringUtils.trim(string);
+    }
 
 }

src/test/java/com/fanruan/api/util/StringKitTest.java

@@ -1,5 +1,6 @@
 package com.fanruan.api.util;
 
+import org.junit.Assert;
 import org.junit.Test;
 
 import static org.junit.Assert.*;
@@ -26,4 +27,13 @@ public class StringKitTest {
     @Test
     public void isNotBlank() {
     }
+    @Test
+    public void trim(){
+        String stringHaveBlank = "  abc  ";
+        String stringWithoutBlank = "abc";
+        String blankString = "   ";
+        Assert.assertEquals(StringKit.trim(stringHaveBlank), "abc");
+        Assert.assertEquals(StringKit.trim(stringWithoutBlank), "abc");
+        Assert.assertEquals(StringKit.trim(blankString), "");
+    }
 }