Cleanup front-end build and python module contents (#1350)

* cleanup build and module contents

* lint

* update chalk

* more cleanup

* fix unit test

server/app/app.py

@@ -1,9 +1,8 @@
-import os
 import datetime
 import logging
 
 from flask import Flask, redirect, current_app, make_response, render_template, abort
-from flask import Blueprint, request, send_from_directory
+from flask import Blueprint, request
 from flask_restful import Api, Resource
 
 from http import HTTPStatus
@@ -76,13 +75,6 @@ def dataset_index(dataset=None):
         )
 
 
-# TODO: remove the top-level /favicon route once the build problem with index.html is resolved
-@webbp.route("/favicon.png", methods=["GET"])
-@webbp.route("/static/img/favicon.png", methods=["GET"])
-def favicon():
-    return send_from_directory(os.path.join(webbp.root_path, "static/img/"), "favicon.png")
-
-
 @webbp.route("/health", methods=["GET"])
 @cache_control_always(no_store=True)
 def health():