Motivation

We've got a report in our Community Slack that we were not enforcing the IfNoneMatch parameter with pre-signed URLs. After a quick investigation, it showed that boto3 was disregarding those parameters during the signing process, leading to us ignoring them and not passing them down to our parser; thus them not being enforced.

This issue shows that Boto3 is not even passing those to the query string parameters of the pre-signed URL: boto/boto3#4367

Changes

• add a new field in the pre-signed URL code to manually pick those values from the query string to pass it back to the headers, for them to be enforced
• add a test directly using botocore because as reported in the boto GH issue, using botocore allows you to properly create a pre-signed URL with the If-None-Match header in the query string