Refactor S3 configuration to be compabitle with ADR and operator-rs implementation

[soenkeliebau]

As a user of the Hive operator I want to refer to an existing S3 connection as specified in stackabletech/documentation#177

This is done when

• the operator is compatible with the ADR linked above to configure our S3 storage (as per the example below)
• documentation, examples and integration tests have been updated

See stackabletech/operator-rs#377 which is required for this