raw_customers.birthday 是字符串，混用了两种日期写法。把它解析成日期类型：
YYYY-MM-DD，例如 2003-04-21；DD/MM/YYYY，日在前、月在后，例如 01/02/1994 是 1994 年 2 月 1 日。其余情况一律为 null，包括：
- 其他写法（如 1990.3.5、3-5-1990、2020/01/02、unknown、-、N/A、空字符串）；
- 格式对但日期不存在的（如 31/04/1999、2023-02-29、12/13/2020）；
- 原本就是 null 的。
数据保证日期字符串前后没有空白，年份都是 4 位。
输入
raw_customers(id, full_name, email, phone, birthday, signup, vip, spend)，所有列都是字符串。输出
列为 id, birthday（birthday 为日期），行数与输入相同（id 可能重复，照常输出），行顺序不限。
raw_customers messy/raw_customers
| # | idstring | full_namestring | emailstring | phonestring | birthdaystring | signupstring | vipstring | spendstring |
|---|---|---|---|---|---|---|---|---|
| 1 | 1 | xu ming | xu.ming60@mail.cn | +86 189 3287 9217 | - | 2025-02-12 | YES | 3428 |
| 2 | 2 | yang guo | yang.guo68@example.com | 10033907579 | 2003-04-21 | 05/01/2025 | n | 2,132.69 |
| 3 | 3 | guo jing | guo.jing91@mail.cn | 15384019161 | 01/02/1994 | 2025-01-01 | Y | 3716.67 |
| 4 | 4 | zhou jie | zhou.jie26@qq.com | 14514506123 | 29/02/2000 | 01/07/2025 | no | 999.73 |
| 5 | 5 | liu yang | liu.yang51@mail.cn | 13049403 | 31/04/1999 | 2025-09-22 | 0 | 2024 |
| 6 | 6 | zhang san | ZHANG.SAN@Example.COM | 13095597297 | 06/07/1978 | 15/11/2025 | no | $1,200.50 |
| 7 | 7 | null | zhou.jie54@example.com | (111) 08436469 | 2003.3.24 | 2025-08-22 | N | $4,809.60 |
| 8 | 8 | BOB smith | N/A | 173-0024-5892 | 11/08/1978 | 2026-06-19 | yes | 4842.25 |
| 9 | 9 | LI WEI | li.wei40@example.com | (109) 17145211 | - | 13/05/2025 | 0 | 3592.13 |
| 10 | 10 | he ping | he.ping54@example.com | 179-0966-9091 | 14/05/1977 | 02/02/2026 | n | 4395.47 |
| 11 | 11 | guo jing | guo.jing4@mail.cn | 19170317974 | 05/05/1993 | 2025-07-27 | 0 | 2,316.99 |
| 12 | 12 | he ping | he.ping86@mail.cn | 136-3363-9532 | 1992-01-23 | 11/10/2025 | N | 1442.64 |
| 13 | 13 | BOB smith | bob.smith67@mail.cn | 1971-11-05 | 2025-07-14 | 1 | $738.58 | |
| 14 | 14 | WANG FANG | wang.fang@@mail.com | N/A | 09/04/1981 | 07/07/2026 | yes | 4152.00 |
| 15 | 15 | grace HOPPER | grace.hopper93@mail.cn | (127) 73068985 | - | 2025-05-07 | YES | 1624 |
| 16 | 16 | guo jing | guo.jing34@qq.com | (105) 81075864 | 2025-02-05 | 0 | 4,802.51 | |
| 17 | 17 | LIU YANG | liu.yang93@qq.com | 17791378 | 16/11/2025 | no | 740.03 | |
| 18 | 18 | GUO JING | guo.jing26@mail.cn | 18180960808 | 04/10/2004 | 2025-06-20 | n | 4196.37 |
| 19 | 19 | zhou jie | zhou.jie17@mail.cn | 167-8513-6904 | 1971-01-07 | 13/01/2025 | 0 | free |
| 20 | 20 | CHEN JING | chen.jing66@qq.com | - | 28/04/2003 | 2025-05-20 | 0 | 1656 |
| # | idString | birthdayDate |
|---|---|---|
| 1 | 1 | null |
| 2 | 2 | 2003-04-21 |
| 3 | 3 | 1994-02-01 |
| 4 | 4 | 2000-02-29 |
| 5 | 5 | null |
| 6 | 6 | 1978-07-06 |
| 7 | 7 | null |
| 8 | 8 | 1978-08-11 |
| 9 | 9 | null |
| 10 | 10 | 1977-05-14 |
| 11 | 11 | 1993-05-05 |
| 12 | 12 | 1992-01-23 |
| 13 | 13 | 1971-11-05 |
| 14 | 14 | 1981-04-09 |
| 15 | 15 | null |
| 16 | 16 | null |
| 17 | 17 | null |
| 18 | 18 | 2004-10-04 |
| 19 | 19 | 1971-01-07 |
| 20 | 20 | 2003-04-28 |
| 21 | 21 | 1982-07-21 |
| 22 | 22 | 1982-03-04 |
| 23 | 23 | 1999-06-24 |
| 24 | 24 | null |
| 25 | 25 | 1994-09-16 |
| 26 | 26 | null |
| 27 | 27 | 1993-09-10 |
| 28 | 28 | 1984-07-24 |
| 29 | 29 | 1993-08-05 |
| 30 | 30 | 1982-11-09 |
| 31 | 31 | 1993-08-16 |
| 32 | 32 | 1981-07-21 |
| 33 | 33 | 1979-04-12 |
| 34 | 34 | 1993-01-12 |
| 35 | 35 | 1971-11-27 |
| 36 | 36 | 1991-06-22 |
| 37 | 37 | 1979-04-24 |
| 38 | 38 | 1972-06-04 |
| 39 | 39 | 1975-08-28 |
| 40 | 40 | null |
| 41 | 41 | 1975-12-19 |
| 42 | 42 | 1999-11-23 |
| 43 | 43 | 1983-10-05 |
| 44 | 44 | 1979-10-04 |
| 45 | 45 | null |
| 46 | 46 | 1988-02-20 |
| 47 | 47 | null |
| 48 | 48 | 1993-04-25 |
| 49 | 49 | 1994-02-19 |
| 50 | 50 | 1988-08-15 |