BUG: able to create nonexistent Timestamp
- [X] I have checked that this issue has not already been reported.

- [X] I have confirmed this bug exists on the latest version of pandas.

- [X] (optional) I have confirmed this bug exists on the master branch of pandas.

---

#### Code Sample, a copy-pastable example

```python
import pandas as pd
ts = pd.Timestamp(year=2001, month=10, day=14, hour=0, minute=30, tz='America/Santiago')
print(ts)
```

#### Problem description

There was a [DST transition](https://www.timeanddate.com/time/change/chile/santiago?year=2001) on the 14th of October 2001, and the time from midnight to 1 a.m. does not exist. Ran into this while working on #40517 where we ran into an error while normalizing a `Timestamp` when midnight does not exist in a particular timezone. Yet, we are able to create this timestamp directly, even though it does not make any sense.

#### Expected Output

I would expect `NonExistentTimeError: 2001-10-14 00:30:00`

#### Notes

I wasn't able to find a prior issue for this. I'm a bit swamped right now, so I would appreciate if someone else looked at this bug. If no one takes it up, I'll investigate next week.

#### Output of ``pd.show_versions()``

<details>

This is on my dev environment, but I'm getting the same behavior on the latest stable version.

INSTALLED VERSIONS
------------------
commit           : 692bba578efb5e305c9b116568e5aad75b3fdbb3
python           : 3.8.8.final.0
python-bits      : 64
OS               : Windows
OS-release       : 10
Version          : 10.0.19041
machine          : AMD64
processor        : Intel64 Family 6 Model 94 Stepping 3, GenuineIntel
byteorder        : little
LC_ALL           : None
LANG             : en_US.UTF-8
LOCALE           : English_United States.1251

pandas           : 0.26.0.dev0+6766.g692bba578e
numpy            : 1.20.1
pytz             : 2021.1
dateutil         : 2.8.1
pip              : 21.0.1
setuptools       : 49.6.0.post20210108
Cython           : 0.29.22
pytest           : 6.2.2
hypothesis       : 6.3.4
sphinx           : 3.5.1
blosc            : None
feather          : None
xlsxwriter       : 1.3.7
lxml.etree       : 4.6.2
html5lib         : 1.1
pymysql          : None
psycopg2         : None
jinja2           : 2.11.3
IPython          : 7.21.0
pandas_datareader: None
bs4              : 4.9.3
bottleneck       : 1.3.2
fsspec           : 0.8.7
fastparquet      : 0.5.0
gcsfs            : 0.7.2
matplotlib       : 3.3.4
numexpr          : 2.7.2
odfpy            : None
openpyxl         : 3.0.6
pandas_gbq       : None
pyarrow          : 3.0.0
pyxlsb           : None
s3fs             : 0.5.2
scipy            : 1.6.0
sqlalchemy       : 1.3.23
tables           : 3.6.1
tabulate         : 0.8.9
xarray           : 0.17.0
xlrd             : 2.0.1
xlwt             : 1.3.0
numba            : 0.52.0

</details>
