Fix tests

Dependencies

• [2] T7Z63K6T hydra: moves jobsetOverview sub
• [*] 2GK5DOU7 * Downloading closures.
• [*] WZ3AEJ67 * hydra_update_gc_roots.pl registers build outputs that should be kept

Change contents

• edit in src/lib/Hydra/Helper/Nix.pm at line 7
  [5.80]

  [2.0]
  + use Config::General;