Writing to redis fails when one of the entities is a timestamp. #5634

Traceback (most recent call last):
  File "/home/user/source_code/feast_exp/b.py", line 38, in <module>
    STORE.write_to_online_store(
  File "/home/user/source_code/feast_exp/.venv/lib/python3.11/site-packages/feast/feature_store.py", line 1736, in write_to_online_store
    provider.ingest_df(feature_view, df)
  File "/home/user/source_code/feast_exp/.venv/lib/python3.11/site-packages/feast/infra/passthrough_provider.py", line 393, in ingest_df
    self.online_write_batch(
  File "/home/user/source_code/feast_exp/.venv/lib/python3.11/site-packages/feast/infra/passthrough_provider.py", line 197, in online_write_batch
    self.online_store.online_write_batch(config, table, data, progress)
  File "/home/user/source_code/feast_exp/.venv/lib/python3.11/site-packages/feast/infra/online_stores/redis.py", line 293, in online_write_batch
    redis_key_bin = _redis_key(
                    ^^^^^^^^^^^
  File "/home/user/source_code/feast_exp/.venv/lib/python3.11/site-packages/feast/infra/online_stores/helpers.py", line 29, in _redis_key
    serialize_entity_key(
  File "/home/user/source_code/feast_exp/.venv/lib/python3.11/site-packages/feast/infra/key_encoding_utils.py", line 140, in serialize_entity_key
    val_bytes, value_type = _serialize_val(
                            ^^^^^^^^^^^^^^^
  File "/home/user/source_code/feast_exp/.venv/lib/python3.11/site-packages/feast/infra/key_encoding_utils.py", line 25, in _serialize_val
    raise ValueError(f"Value type not supported for feast feature store: {v}")
ValueError: Value type not supported for feast feature store: unix_timestamp_val: 1758823656

import datetime

import pandas as pd

from feast import FeatureView, Field, Entity
from feast.types import Int32
from feast.infra.offline_stores.contrib.postgres_offline_store.postgres_source import PostgreSQLSource
from feast import ValueType

from utils.feast_utils import STORE

e2 = Entity(name="e2", value_type=ValueType.UNIX_TIMESTAMP,description="e2")

source_one_ts=PostgreSQLSource(
        name=f"one_ts",
        table="one_ts",
        timestamp_field="event_timestamp",
        created_timestamp_column="created_at",
    )
one_ts = FeatureView(
    description="Description",
    entities=[
        e2
    ],
    schema=[
        Field(name="f1", dtype=Int32)
    ],
    name="one_ts",
    source=source_one_ts
)


if __name__ == "__main__":
    STORE.delete_feature_view(one_ts.name)
    items_to_apply = [e2, one_ts, source_one_ts]
    STORE.apply(items_to_apply)

    STORE.write_to_online_store(
                feature_view_name=one_ts.name,
                inputs=pd.DataFrame(
                    [
                        {
                            "event_timestamp": datetime.datetime.now(),
                            "created_at": datetime.datetime.now(),
                            "f1": 12,
                            "e2": datetime.datetime.now(),
                        }
                    ]
                ),
            )