Merge pull request #2652 from yuuch/update_show_processlist_doc

add memory_usage column for show processlist doc

Author: BohuTANG

website/databend/docs/sqlstatement/show-commands/show-processlist.md

@@ -17,10 +17,10 @@ SHOW PROCESSLIST
 
 ```
 mysql> SHOW PROCESSLIST;
-+--------------------------------------+-----------------+-------+----------+------------------+
-| id                                   | host            | state | database | extra_info       |
-+--------------------------------------+-----------------+-------+----------+------------------+
-| 1e6e5ed4-5441-43da-9ed6-eb6ba9baeb64 | 127.0.0.1:60080 | Query | default  | show processlist |
-| 3d283add-4f60-416d-b9ca-662120614093 | 127.0.0.1:57018 | Query | default  | NULL             |
-+--------------------------------------+-----------------+-------+----------+------------------+
++--------------------------------------+-----------------+-------+----------+------------------+------------------+
+| id                                   | host            | state | database | extra_info       | memory_usage     |
++--------------------------------------+-----------------+-------+----------+------------------+------------------+
+| 1e6e5ed4-5441-43da-9ed6-eb6ba9baeb64 | 127.0.0.1:60080 | Query | default  | show processlist | 1234567891011121 |
+| 3d283add-4f60-416d-b9ca-662120614093 | 127.0.0.1:57018 | Query | default  | NULL             | 1234567891011121 |
++--------------------------------------+-----------------+-------+----------+------------------+------------------+
 ```