nixos: add preferLocalBuild=true; on derivations for config files

nixos/modules/services/databases/hbase.nix

@@ -18,7 +18,7 @@ let
     </configuration>
   '';
 
-  configDir = pkgs.runCommand "hbase-config-dir" {} ''
+  configDir = pkgs.runCommand "hbase-config-dir" { preferLocalBuild = true; } ''
     mkdir -p $out
     cp ${cfg.package}/conf/* $out/
     rm $out/hbase-site.xml

nixos/modules/services/databases/influxdb.nix

@@ -98,6 +98,7 @@ let
 
   configFile = pkgs.runCommand "config.toml" {
     buildInputs = [ pkgs.remarshal ];
+    preferLocalBuild = true;
   } ''
     remarshal -if json -of toml \
       < ${pkgs.writeText "config.json" (builtins.toJSON configOptions)} \