hydra-eval-jobs: fix maintainer resolution

Dependencies

• [2] ALU52WZJ Handle attrsets in meta.license (i.e. lib.licenses)
• [3] OC4Q4PXC Sync with nixUnstable
• [4] ZTQEU5QS Hydra: Add support for maxSilent meta attribute (also already added timeout, but not implemented the actual timeout for the build yet)
• [5] HVXL2XUZ
• [6] 5X6FHW3S hydra-eval-jobs: Fix building against the latest unstable Nix
• [7] 4GTOWRFW hydra-eval-jobs: Fix build
• [8] STZE4KKR Fix build against Nix master
• [9] DPYJFBXU hydra-eval-jobs: Support meta.license being a list
• [10] 7YCFGMZB * Report evaluation errors per job, and don't bail out if a job fails
• [11] 5DYPEBSI hydra-eval-jobs: Use function argument default values
• [*] 4N5APGRG * Start of a helper tool to evaluate job expressions efficiently.

Change contents

• replacement in src/hydra-eval-jobs/hydra-eval-jobs.cc at line 32
  [4.221]→[4.0:86](∅→∅)
  − static string queryMetaStrings(EvalState & state, DrvInfo & drv, const string & name)
  [4.1]

  [4.294]
  + static string queryMetaStrings(EvalState & state, DrvInfo & drv, const string & name, const string & subAttribute)
• replacement in src/hydra-eval-jobs/hydra-eval-jobs.cc at line 45
  [2.350]→[2.350:421](∅→∅)
  − auto a = v.attrs->find(state.symbols.create("shortName"));
  [2.350]

  [2.421]
  + auto a = v.attrs->find(state.symbols.create(subAttribute));
• replacement in src/hydra-eval-jobs/hydra-eval-jobs.cc at line 120
  [3.424]→[3.424:499](∅→∅)
  − res.attr("license", queryMetaStrings(state, *drv, "license"));
  [3.424]

  [3.499]
  + res.attr("license", queryMetaStrings(state, *drv, "license", "shortName"));
• replacement in src/hydra-eval-jobs/hydra-eval-jobs.cc at line 122
  [3.567]→[3.567:650](∅→∅)
  − res.attr("maintainers", queryMetaStrings(state, *drv, "maintainers"));
  [3.567]

  [3.650]
  + res.attr("maintainers", queryMetaStrings(state, *drv, "maintainers", "email"));