S3 provider SSE-C not working since parameters (key) is not passed to Boto3

[greenstatic]

When we enable SSE-C for the S3 provider using the following settings:

AWS_S3_OBJECT_PARAMETERS = {
    "SSECustomerAlgorithm": "AES256",
    "SSECustomerKey": "<redacted key>",
    "SSECustomerKeyMD5": "<redacted md5 key>"
}

We can successfully save a file to S3 (Minio) but when we try to retrieve it, we get a generic error.
The file however is normally accessible using the aws-cli when supplied with the correct encryption keys.
Meaning django-storages handles saving files using encryption just fine, but doesn't read them correctly.

I dived into the code and found 2 issues when reading files from S3.

1. The first HEAD request (https://github.com/jschneier/django-storages/blob/master/storages/backends/s3boto3.py#L74) does not contain the necessary parameters (i.e. AWS_S3_OBJECT_PARAMETERS that contain the necessary headers).
   Adding the encryption keys to the HEAD request is required as per AWS S3 documentation:

If you encrypt an object by using server-side encryption with customer-provided encryption keys (SSE-C) when you store the object in Amazon S3, then when you retrieve the metadata from the object, you must use the following headers:

• x-amz-server-side​-encryption​-customer-algorithm
• x-amz-server-side​-encryption​-customer-key
• x-amz-server-side​-encryption​-customer-key-MD5

2. Once 1. is fixed, we still get an error because when we fetch the contents of the file (https://github.com/jschneier/django-storages/blob/master/storages/backends/s3boto3.py#L100), we do so again without passing params (AWS_S3_OBJECT_PARAMETERS) to boto3