d175b70 test-fileio: add test for return value of read_one_line_file()

Authored and Committed by zbyszek a year ago
    test-fileio: add test for return value of read_one_line_file()
    
    Prompted by https://github.com/systemd/systemd/pull/26904#pullrequestreview-1349890241.
    
        
file modified
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