[Doc][Improve] Intro the multi-line text feature in document (#6713)

Author: nianhua99

Diff for: docs/en/concept/config.md

@@ -64,6 +64,19 @@ sink {
 }
 ```
 
+#### multi-line support
+
+In `hocon`, multiline strings are supported, which allows you to include extended passages of text without worrying about newline characters or special formatting. This is achieved by enclosing the text within triple quotes **`"""`** . For example:
+
+```
+var = """
+Apache SeaTunnel is a
+next-generation high-performance,
+distributed, massive data integration tool.
+"""
+sql = """ select * from "table" """
+```
+
 ### json
 
 ```json

Diff for: docs/zh/concept/config.md

@@ -68,6 +68,19 @@ sink {
 }
 ```
 
+#### 多行文本支持
+
+`hocon`支持多行字符串，这样就可以包含较长的文本段落，而不必担心换行符或特殊格式。这可以通过将文本括在三层引号 **`"""`** 中来实现。例如:
+
+```
+var = """
+Apache SeaTunnel is a
+next-generation high-performance,
+distributed, massive data integration tool.
+"""
+sql = """ select * from "table" """
+```
+
 ### json
 
 ```json