In push_prometheus_alert function using http protocol can be insecure

[vineela1999]

Issue/Feature Description:
In delfin/exporter/prometheus/alert_manager.py,
In the function definition,
def push_prometheus_alert(self, alerts):

try:
                response = requests.post('http://' + host + ":" + port +
                                         '/api/v1/alerts',
                                         json=self.alerts)
                if response.status_code != 200:

here using Http protocol can be insecure

Why this issue to fixed / feature is needed(give scenarios or use cases):
Using Http protocol can be insecure . Https can be used instead
How to reproduce, in case of a bug:

Other Notes / Environment Information: (Please give the env information, log link or any useful information for this issue)