Fix badly formatted table

Author: Blargian

docs/en/sql-reference/statements/select/join.md

@@ -317,6 +317,7 @@ USING (equi_column1, ... equi_columnN, asof_column)
 
 For example, consider the following tables:
 
+```text
          table_1                           table_2
       event   | ev_time | user_id       event   | ev_time | user_id
     ----------|---------|---------- ----------|---------|----------
@@ -325,6 +326,7 @@ For example, consider the following tables:
                   ...                 event_2_2 |  12:30  |   42
     event_1_2 |  13:00  |  42         event_2_3 |  13:00  |   42
                   ...                               ...
+```
 
 `ASOF JOIN` can take the timestamp of a user event from `table_1` and find an event in `table_2` where the timestamp is closest to the timestamp of the event from `table_1` corresponding to the closest match condition. Equal timestamp values are the closest if available. Here, the `user_id` column can be used for joining on equality and the `ev_time` column can be used for joining on the closest match. In our example, `event_1_1` can be joined with `event_2_1` and `event_1_2` can be joined with `event_2_3`, but `event_2_2` can't be joined.