title: Airflow service host in docker-compose can't change time zone
body: <p>I would like to change the time zone of airflow from UTC to my current time zone(UTC+8 / Asia/Macau), and mark the DAG will run in Macau midnight not UTC midnight ( coz run in UTC midnight it make the data create time always be come previous day not today)</p>
  <p>However I tried many method it still not work, I tried:</p>
  <p>change DockerFile of the airflow project</p>
  <pre><code># Airflow configurations
  ENV AIRFLOW_HOME=/app/project/brownian
  ENV AIRFLOW__CORE__LOAD_EXAMPLES=False
  ENV AIRFLOW__CORE__LOGGING_LEVEL=DEBUG
  ENV AIRFLOW__CORE__DAGS_FOLDER=/app/project/brownian/brownian/dags
  ENV AIRFLOW__SCHEDULER__MIN_FILE_PROCESS_INTERVAL=60
  ENV AIRFLOW__SCHEDULER__SCHEDULER_MAX_THREADS=3
  ENV AIRFLOW__CORE__DEFAULT_TIMEZONE=Asia/Macau
  ENV AIRFLOW__WEBSERVER__DEFAULT_UI_TIMEZONE=Asia/Macau
  </code></pre>
  <p>Also tried to only change the DAG time znoe</p>
  <pre><code>tz = pytz.timezone('Asia/Macau')
  
  
  def localize_utc_tz(d):
      return tz.fromutc(d)
  
  default_args = {
      &quot;start_date&quot;:datetime(2020, 7, 20),
  }
  
  dag = DAG(&quot;scrap_sns&quot;, default_args=default_args, schedule_interval=&quot;@daily&quot;,
            user_defined_filters={
                'localtz': localize_utc_tz,
            })
  </code></pre>
  <p>However both of them are not work, the time show in airflow still is UTC, and the DAG still run in UTC midnight not my position midnight.</p>
  <p>And method I can try?</p>
  <p>Or on the other hand, I just want the scheduler run in UTC+8 midnight, could I change the code/ something to achieve this target?</p>