set port to use env

Author: rhnmht30

index.js

@@ -45,7 +45,7 @@ app.use("/api/v1/blogs", require("./routes/api/v1/blogs"));
 app.use("/api/v1/contests", require("./routes/api/v1/contests"));
 app.use("/api/v1/admin", require("./routes/api/v1/admin"));
 
-app.listen(7002, err => {
+app.listen(process.env.PORT, err => {
   if (err) {
     console.log("Error in running server");
     return;