d3b82f5 Add tests for verify_valid_installtree function (#1844287)

Authored and Committed by jkonecny 3 years ago
    Add tests for verify_valid_installtree function (#1844287)
    
    It's testing if repodata/repomd.xml file exists.
    
    Related: rhbz#1844287
    Related: rhbz#1849093