Currently, Doris has a variety of readers for different file formats,
such as parquet reader, orc reader, csv reader, json reader and so on.
The interfaces of these readers are not unified, which makes it impossible to call them through a unified method.
In this PR, I added a `GenericReader` interface class, and other Readers will implement this interface class
to use the `get_next_block()` method.
This PR currently only modifies `arrow_reader` and `parquet reader`.
Other readers will be modified one by one in subsequent PRs.
Something the upstream system(eg, hive) may create empty orc file
which only has a header and footer, without schema.
And if we call `_reader->createRowReader()` with selected columns,
it will throw ParserError: Invalid column selected xx.
So here we first check its number of rows and skip these kind of files.
This is only a fix for non-vec load, for vec load, it use arrow scanner
to read orc file, which does not have this problem.
