Merge branch 'update-nixpkgs' into 'develop'

Weekly nixpkgs updateUpdate nixpkgs.

See merge request !205

nixpkgs-2105.json

 {
   "name": "release2105",
-  "url": "https://releases.nixos.org/nixos/21.05/nixos-21.05.3801.83667ff60a8/nixexprs.tar.xz",
-  "sha256": "10gccdacm10pp3kdvjhgiclnxl6c518vy5amjjbpy684hfgl0xi8"
+  "url": "https://releases.nixos.org/nixos/21.05/nixos-21.05.3916.3b1789322fc/nixexprs.tar.xz",
+  "sha256": "16czbb0kifzfxhg9g89d06csnfand7hjw829xbylbggmj9b8givq"
 }