Split off of #9835.
The series removes extraneous includes of lister.hh from header files
and adds a unit test for lister::scan_dir to test throwing an exception
from the walker function passed to `scan_dir`.
Test: unit(dev)
Closes#9885
* github.com:scylladb/scylla:
test: add lister_list
lister: add more overloads of fs::path operator/ for std::string and string_view
resource_manager: remove unnecessary include of lister.hh from header file
sstables: sstable_directory: remove unncessary include of lister.hh from header file