MDEV-19887: Document --copy-s3-tables option on mysqldump man page

Closes PR #1385

man/mysqldump.1

@@ -499,6 +499,22 @@ Compress all information sent between the client and the server if both support
 .sp -1
 .IP \(bu 2.3
 .\}
+.\" mysqldump: copy-s3-tables option
+.\" copy-s3-tables option: mysqldump
+\fB\-\-copy\-s3\-tables\fR
+.sp
+By default S3 tables are ignored\&. With this option set, the result file will contain a CREATE statement 
+for a similar Aria table, followed by the table data and ending with an ALTER TABLE xxx ENGINE=S3\&.
+.RE
+.sp
+.RS 4
+.ie n \{\
+\h'-04'\(bu\h'+03'\c
+.\}
+.el \{\
+.sp -1
+.IP \(bu 2.3
+.\}
 .\" mysqldump: create-options option
 .\" create-options option: mysqldump
 \fB\-\-create\-options\fR,