Remove monotonic

> On Python 3.3 or newer, monotonic will be an alias of time.monotonic
> from the standard library. On older versions, it will fall back to an
> equivalent implementation.

– https://pypi.org/project/monotonic/

app/clients/email/aws_ses.py

@@ -1,7 +1,7 @@
 import boto3
 import botocore
 from flask import current_app
-from monotonic import monotonic
+from time import monotonic
 from notifications_utils.recipients import InvalidEmailError
 
 from app.clients import STATISTICS_DELIVERED, STATISTICS_FAILURE

app/clients/sms/firetext.py

@@ -1,7 +1,7 @@
 import json
 import logging
 
-from monotonic import monotonic
+from time import monotonic
 from requests import request, RequestException
 
 from app.clients.sms import (SmsClient, SmsClientResponseException)

app/clients/sms/mmg.py

@@ -1,5 +1,5 @@
 import json
-from monotonic import monotonic
+from time import monotonic
 from requests import (request, RequestException)
 from app.clients.sms import (SmsClient, SmsClientResponseException)