BUG: pivot_table chokes on pd.DatetimeTZDtype if there are no rows.

[pcorpet]

Pandas version checks

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Reproducible Example

import pandas as pd
df = pd.DataFrame({'timestamp': [pd.Timestamp('2024-01-01T00:00', tz='UTC')], 'category': ['A'], 'value': [100]})
df[df.category == "C"].pivot_table(index="category", columns="value", values="timestamp")

Issue Description

This raises an error TypeError: Cannot interpret 'datetime64[ns, UTC]' as a data type

Expected Behavior

It should return an empty DataFrame.

Installed Versions

INSTALLED VERSIONS ------------------ commit : d9cdd2ee5a58015ef6f4d15c7226110c9aab8140 python : 3.12.3.final.0 python-bits : 64 OS : Darwin OS-release : 23.5.0 Version : Darwin Kernel Version 23.5.0: Wed May 1 20:14:38 PDT 2024; root:xnu-10063.121.3~5/RELEASE_ARM64_T6020 machine : arm64 processor : arm byteorder : little LC_ALL : None LANG : fr_FR.UTF-8 LOCALE : fr_FR.UTF-8 pandas : 2.2.2 numpy : 1.26.4 pytz : 2024.1 dateutil : 2.9.0.post0 setuptools : 69.5.1 pip : 24.0 Cython : None pytest : 8.2.1 hypothesis : None sphinx : None blosc : None feather : None xlsxwriter : 3.2.0 lxml.etree : 5.2.1 html5lib : None pymysql : None psycopg2 : 2.9.9 jinja2 : 3.1.4 IPython : 8.23.0 pandas_datareader : None adbc-driver-postgresql: None adbc-driver-sqlite : None bs4 : 4.12.3 bottleneck : None dataframe-api-compat : None fastparquet : None fsspec : 2024.5.0 gcsfs : None matplotlib : 3.8.4 numba : None numexpr : None odfpy : None openpyxl : 3.1.0 pandas_gbq : None pyarrow : 16.1.0 pyreadstat : None python-calamine : None pyxlsb : None s3fs : 2024.5.0 scipy : None sqlalchemy : 2.0.30 tables : None tabulate : 0.9.0 xarray : None xlrd : None zstandard : None tzdata : 2024.1 qtpy : None pyqt5 : None