Quick hack to fix compilation

Dependencies

• [2] PW4TLMWS Sync with latest Nix
• [3] 5CNQUQ77 Bump Nix
• [4] BYVRA54Q Temporarily disable machines on any exception, not just connection failures
• [5] BUEWVH2M Remove signing parameter (nix#f435f82)
• [6] WV4SSAIY Build against nix-master
• [7] EBJP3MNA Build against nix-master
• [8] H46LUUZY hydra-queue-runner: don't try to distribute builds on localhost
• [9] UVNTWTWG Prevent download of NARs we just uploaded
• [*] 5AIYUMTB Basic remote building

Change contents

• replacement in src/hydra-queue-runner/build-remote.cc at line 447
  [3.8870]→[2.101:173](∅→∅)
  − destStore->importPaths(from, result.accessor, NoCheckSigs);
  [3.8870]

  [3.231]
  + destStore->importPaths(from, /* result.accessor, */ NoCheckSigs);