allow users with 'restart-jobs' role to restart individual builds

Dependencies

• [2] VHV6GI4L Add a jobset eval action to restart all aborted/cancelled builds
• [3] ZILILXXK * Allow scheduled builds to be cancelled. They're not removed from
• [4] A52HEFHQ * Allow builds to be restarted (if they failed with a transient error,
• [5] OSVLMLCQ hydra: factored out build restart and
• [6] GJFYEU3S * Nix now stores logs by default as bzip2, make sure the build page uncompresses before showing.
• [*] LBNVQXUB * Build the /build stuff in a separate controller.

Change contents

• replacement in src/lib/Hydra/Controller/Build.pm at line 496
  [3.184]→[3.184:230](∅→∅)
  − requireProjectOwner($c, $build->project);
  [3.183]

  [2.0]
  + requireRestartPrivileges($c, $build->project);