Fix linting errors

app/clients/cbc_proxy.py

@@ -134,7 +134,7 @@ class CBCProxyClientBase(ABC):
                 InvocationType='RequestResponse',
                 Payload=payload_bytes,
             )
-        except botocore.exceptions.ClientError as exc:
+        except botocore.exceptions.ClientError:
             current_app.logger.exception(f'Boto ClientError calling lambda {lambda_name}')
             success = False
             return success

app/clients/email/aws_ses.py

@@ -2,7 +2,6 @@ import boto3
 import botocore
 from flask import current_app
 from time import monotonic
-from notifications_utils.recipients import InvalidEmailError
 
 from app.clients import STATISTICS_DELIVERED, STATISTICS_FAILURE
 from app.clients.email import EmailClient, EmailClientException, EmailClientNonRetryableException