Currently minio starts with a bucket that has public anonymous access. Respectively, all tests use unsigned S3 requests. That was done for simplicity, and its better to apply some policy to the bucket and, consequentially, make tests sign their requests.
Other than the obvious benefit that we test requests signing in unit tests, another goal of this PR is to make it possible to simulate and test various error paths locally, e.g. #13745 and #13022Closes#14525
* github.com:scylladb/scylladb:
test/s3: Remove AWS_S3_EXTRA usage
test/s3: Run tests over non-anonymous bucket
test/minio: Create random temp user on start
code: Rename S3_PUBLIC_BUCKET_FOR_TEST
89ba4e4a5e