Add support for insecure S3 backup endpoints

Problem to solve

Unable to push backups to an S3 compatible bucket with self signed certificates.

Further details

In a self hosted k8s/kind cluster the backup pod completes after timing out trying to push to a S3 compatible endpoint. The backup job returns as failed with the following error: ”: x509: certificate signed by unknown authority\nERROR: 2022/04/08 20:17:26.729366 Unable to continue the backup process because of the loss of a part 1.\ncommand terminated with exit code 1

EDIT - There also seems to be an issue escaping special characters in the endpoint string. ie "my-s3-bucket.dev.local" using dashes produces a parsing error.

Proposal

Add support for https insecure S3 compatible endpoints.