Slow query log: Field 'Last_errno:' should be used for errors only

Start Percona Server 8.0 with slow query log enabled:

--loose-log_slow_verbosity=full --slow_query_log=1 --long_query_time=0

Execute following statements:

mysql -uroot test

mysql> create table t1(f1 decimal(5,2) not null);

mysql>INSERT INTO t1(f1) values (31.400191);

Row was successfully inserted but also we got a warning with error code 1265. This warning was logged into the slow query log as value for 'Last_errno' field (see below) but that field should represent only real errors and not a warnings.

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Time: 2019-12-18T18:53:15.857371Z

1. [email protected]: root[root] @ localhost [] Id: 40167
2. Schema: test Last_errno: 1265 Killed: 0
3. Query_time: 0.000593 Lock_time: 0.000101 Rows_sent: 0 Rows_examined: 0 Rows_affected: 1
4. Bytes_sent: 11 Tmp_tables: 0 Tmp_disk_tables: 0 Tmp_table_sizes: 0
5. InnoDB_trx_id: 32015
6. Full_scan: No Full_join: No Tmp_table: No Tmp_table_on_disk: No
7. Filesort: No Filesort_on_disk: No Merge_passes: 0
8. InnoDB_IO_r_ops: 0 InnoDB_IO_r_bytes: 0 InnoDB_IO_r_wait: 0.000000
9. InnoDB_rec_lock_wait: 0.000000 InnoDB_queue_wait: 0.000000
10. InnoDB_pages_distinct: 5
    SET timestamp=1576695195;
    INSERT INTO t1(f1) values (31.400191);

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Slow query log should be fixed  to separate errors from warnings and report only errors in 'Last_errno' field.