add catalog schema，解决sql 1142的问题

SHOW INDEX FROM `table` FROM mysql
> 1142 - SELECT command denied to user ''@'' for table 'channel'

mybatis-plus-extension/src/main/java/com/baomidou/mybatisplus/extension/plugins/IllegalSQLInterceptor.java

@@ -267,7 +267,9 @@ public class IllegalSQLInterceptor implements Interceptor {
             ResultSet rs;
             try {
                 DatabaseMetaData metadata = conn.getMetaData();
-                rs = metadata.getIndexInfo(dbName, dbName, tableName, false, true);
+                String catalog = StringUtils.isEmpty(dbName)? conn.getCatalog():dbName;
+                String schema = StringUtils.isEmpty(dbName)? conn.getSchema():dbName;
+                rs = metadata.getIndexInfo(catalog, schema, tableName, false, true);
                 indexInfos = new ArrayList<>();
                 while (rs.next()) {
                     //索引中的列序列号等于1，才有效