Add a patch to handle badly formed XLS files

[elliotcm]

This pull request addresses an edge case in reading Excel XLS files where some writers emit ROW records with empty cell ranges, which previously led to incorrect row data being returned. The fix ensures that valid cell data is preserved even when such ROW records are encountered. The most important changes are grouped below:

Bug Fix for Reading Rows with Empty Cell Ranges:

• Updated set_row_address in lib/spreadsheet/excel/reader.rb to preserve the original row offset and block when a ROW record has first_used == first_unused but cell data exists, preventing incorrect seeking and empty row results.

Internal API changes:

• Exposed the row_addresses attribute in Spreadsheet::Excel::Worksheet to allow tracking and referencing row offsets during parsing.

Test Coverage:

• Added a new integration test test_row_record_with_empty_cell_range in test/integration.rb to verify that rows with cell data are correctly read even when the ROW record claims no cells.

The sample file is generated from scratch in order to be anonymous, but it has been tested against a full original file that exhibits the issue.

[zdavatz]

Thank you for the PR! Will do a new release now!

[zdavatz]

Successfully registered gem: spreadsheet (1.3.5)

[elliotcm]

@zdavatz Thanks!