Don't display rows affected when the connector tells us -1

[dhashe]

Description

We have been displaying "0 rows affected" in this case, but that is
misleading for CTEs, which could affect any number of rows.

Fixes #203

Manual Testing

(venv) dhashe@Aurelius litecli $ litecli -D :memory:
LiteCli: 1.14.3.dev1+geedfef6 (SQLite: 3.37.2)
GitHub: https://github.com/dbcli/litecli
:memory:> create table data (
              id INTEGER PRIMARY KEY
          );
Query OK
Time: 0.001s
:memory:> with temp as (
              select 1 as id
          )
          insert into data select id from temp;
Query OK
Time: 0.001s
:memory:> select * from data;
+----+
| id |
+----+
| 1  |
+----+
1 row in set
Time: 0.017s
:memory:> update data set id = 2;
Query OK, 1 row affected
Time: 0.001s
:memory:> insert into data (id) values (3), (4);
Query OK, 2 rows affected
Time: 0.001s
:memory:>

Checklist

• I've added this contribution to the CHANGELOG.md file.

[amjith]

Thank you for the contribution. I appreciate you taking the time to fix it. 🍦

I noticed in your original issue you #203 you invoke litecli with the -D option. That might be redundant. You can do litecli :memory: which is the same as using the -D option.