keep sign profile by default

Author: mprzytulski

serverless/service/plugins/code_sign.py

@@ -16,7 +16,7 @@ def __init__(
         source_key=None,
         destination_bucket=None,
         destination_prefix=None,
-        retain=False,
+        retain=True,
     ):
         super().__init__("serverless-aws-signer")
         self.profile = profile