fix(redis): Support list types in RedisBuffer serialization

[sentry]

This PR addresses a TypeError: <class 'list'> occurring in sentry.tasks.store.save_event when RedisBuffer._dump_value attempts to serialize Group.data.

The root cause was that RedisBuffer._dump_value did not have a specific branch to handle Python list types. This became problematic when Group.data.metadata.seer_similarity.results (which is a list of dicts from Seer) was encountered during serialization, causing the else branch to raise a TypeError.

This fix introduces elif isinstance(value, list) branches in both _dump_value and _load_value to correctly serialize and deserialize list types, mirroring the existing dict handling. Additionally, the return type annotation for _load_values was updated to include list[Any] to resolve a mypy error.

New test cases have been added to test_dump_and_load_value to cover both flat lists and lists of dictionaries, ensuring the new serialization logic works as expected.

Fixes SENTRY-5SD4

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Fixes SENTRY-5SD4

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