Fix build

Dependencies

• [2] NSBNNM77 Add hydra.conf option "nar_buffer_size" to configure memoryTokens limit
• [*] 24BMQDZA Start of single-process hydra-queue-runner
• [*] OCZ4LSGG Automatically retry aborted builds
• [*] ENXUSMSV Make concurrency more robust

Change contents

• edit in src/hydra-queue-runner/hydra-queue-runner.cc at line 18
  [4.5058]

  [5.1078]
  +
• edit in src/hydra-queue-runner/hydra-queue-runner.cc at line 20
  [5.1079]

  [6.21]
  + namespace nix {
• edit in src/hydra-queue-runner/hydra-queue-runner.cc at line 22
  [6.22]

  [2.0]
  + template<> void toJSON<std::atomic<long>>(std::ostream & str, const std::atomic<long> & n) { str << n; }

  + template<> void toJSON<std::atomic<unsigned long>>(std::ostream & str, const std::atomic<unsigned long> & n) { str << n; }

  + template<> void toJSON<double>(std::ostream & str, const double & n) { str << n; }

  +

  + }

  +

  +