Add rowcount property for Python cursor objects

[hannes]

as the law has commanded

[Mause]

Hah, that'll do it yeah 😁

[Tishj]

Looks good to me, we can extend this with actual logic whenever, for now just having the method reduces the threshold for that 👍

[Tishj]

Ah I think you ran regenerate_python_stubs.sh, which should probably be deleted actually
It breaks all the manual changes made, instead we just modify the stubs manually

I think you instead just want to add:

rowcount: int

To the list in duckdb-stubs/__init__pyi that contains:

apilevel: str
comment: token_type
default_connection: DuckDBPyConnection
identifier: token_type
keyword: token_type
numeric_const: token_type
operator: token_type
paramstyle: str
string_const: token_type
threadsafety: int