src: remove using v8::Function in node_os.cc

PR-URL: #25640
Reviewed-By: Denys Otrishko <shishugi@gmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>

Author: cjihrig

src/node_os.cc

@@ -52,7 +52,6 @@ using v8::ArrayBuffer;
 using v8::Boolean;
 using v8::Context;
 using v8::Float64Array;
-using v8::Function;
 using v8::FunctionCallbackInfo;
 using v8::Int32;
 using v8::Integer;