"has_header" in "read_options" for `read_excel` has inconsistent behavior across engines

Checks

[X] I have checked that this issue has not already been reported.
[X] I have confirmed this bug exists on the latest version of Polars.

Reproducible example

If I use the default engine option ("xlsx2csv") it returns the expected result Code:

pl_data = pl.read_excel(
    "example.xlsx", read_options={"has_header": False}, sheet_name="Sheet1"
)

Result:

If I use "openpyxl" as the engine, it returns an unexpected result Code:

pl_data = pl.read_excel(
    "example.xlsx", read_options={"has_header": False}, sheet_name="Sheet1", engine="openpyxl"
)

Result:

File used: example.xlsx

Log output

No response

Issue description

When I use the default engine xlsx2csv to read the Excel file without header, it returns the correct result, with the "supposed" header being one of the rows in the DataFrame. But when I switch to openpyxl (the engine I'm using) and read the file again, also with no header, the "supposed" header is now read as the header and not one of the rows of the DataFrame. I have provided images and code to reproduce.

Expected behavior

I want to use openpyxl as my engine and read the Excel file without a header. I expect the 1st row in the example.xlsx file to be 1 of the row in the DataFrame and not as the DataFrame header.

Installed versions

``` --------Version info--------- Polars: 0.20.31 Index type: UInt32 Platform: macOS-13.6.3-arm64-arm-64bit Python: 3.11.7 (main, Dec 4 2023, 18:10:11) [Clang 15.0.0 (clang-1500.1.0.2.5)] ----Optional dependencies---- adbc_driver_manager: cloudpickle: 3.0.0 connectorx: deltalake: fastexcel: fsspec: 2023.12.2 gevent: 23.7.0 hvplot: matplotlib: 3.9.0 nest_asyncio: 1.5.9 numpy: 1.26.4 openpyxl: 3.1.2 pandas: 1.3.5 pyarrow: 14.0.2 pydantic: pyiceberg: pyxlsb: sqlalchemy: 2.0.16 torch: xlsx2csv: xlsxwriter: 3.2.0 ```

pola-rs / polars