[C++][Arrow Flight SQL ODBC] Fix value for `lpstrFilter`

[alinaliBQ]

Describe the enhancement requested

From https://learn.microsoft.com/en-us/windows/win32/api/commdlg/ns-commdlg-openfilenamea:

To retrieve a shortcut's target without filtering, use the string "All Files\0*.*\0\0".

AC:

arrow/cpp/src/arrow/flight/sql/odbc/odbc_impl/ui/dsn_configuration_window.cc

Lines 569 to 570 in bab5580

	// TODO: What type should this be?
	open_file_name.lpstrFilter = L"All\0*.*";

In above code, replace All\0*.* with "All Files\0*.*\0\0". Since ODBC is using unicode, using the wide character string is the correct choice here. \

Parent issue: #30622

Component(s)

C++, FlightRPC