Queue monitor: Get only the fields we need

Dependencies

• [2] ATJ54SPX Use PostgreSQL notifications for queue events
• [3] 2IQRXLWE Support cancelling builds
• [4] ENXUSMSV Make concurrency more robust
• [5] 24BMQDZA Start of single-process hydra-queue-runner

Change contents

• replacement in src/hydra-queue-runner/hydra-queue-runner.cc at line 427
  [3.1925]→[2.1516:1641](∅→∅)
  − auto res = txn.parameterized("select * from Builds where id > $1 and finished = 0 order by id")(lastBuildId).exec();
  [3.1836]

  [3.9906]
  + auto res = txn.parameterized("select id, project, jobset, job, drvPath from Builds where id > $1 and finished = 0 order by id")(lastBuildId).exec();