Remove superfluous check

Dependencies

• [2] HPJKBFZ4 Handle concurrent finishing of the same build
• [3] 24BMQDZA Start of single-process hydra-queue-runner
• [4] 5AIYUMTB Basic remote building
• [5] FQQRJUO4 Mark builds as busy
• [6] 62MQPRXC Pass null values to libpqxx properly

Change contents

• replacement in src/hydra-queue-runner/hydra-queue-runner.cc at line 217
  [3.600]→[2.1709:1909](∅→∅)
  − ("update Builds set finished = 1, busy = 0, buildStatus = $2, startTime = $3, stopTime = $4, size = $5, closureSize = $6, releaseName = $7, isCachedBuild = $8 where id = $1 and finished = 0")
  [3.600]

  [3.18032]
  + ("update Builds set finished = 1, busy = 0, buildStatus = $2, startTime = $3, stopTime = $4, size = $5, closureSize = $6, releaseName = $7, isCachedBuild = $8 where id = $1")