[refactor][doc]The new version of the document is online (#9272)

replace the `docs/` with `new-docs/`

docs/en/sql-manual/sql-functions/string-functions/regexp/regexp_replace.md

@@ -0,0 +1,54 @@
+---
+{
+    "title": "regexp_replace",
+    "language": "en"
+}
+---
+
+<!-- 
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied.  See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+
+# regexp_replace
+## description
+### Syntax
+
+`VARCHAR regexp_replace(VARCHAR str, VARCHAR pattern, VARCHAR repl)`
+
+
+Regular matching of STR strings, replacing the part hitting pattern with repl
+
+## example
+
+```
+mysql> SELECT regexp_replace('a b c', " ", "-");
++-----------------------------------+
+| regexp_replace('a b c', ' ', '-') |
++-----------------------------------+
+| a-b-c                             |
++-----------------------------------+
+
+mysql> SELECT regexp_replace('a b c','(b)','<\\1>');
++----------------------------------------+
+| regexp_replace('a b c', '(b)', '<\1>') |
++----------------------------------------+
+| a <b> c                                |
++----------------------------------------+
+```
+## keyword
+REGEXP_REPLACE,REGEXP,REPLACE