implement IAM role support for S3 connector (#9)

* implement IAM role support for S3 connector

0.1.4-test

let assume role session duration to be set as default 15 minutes

bump guava version (#2)

* Bump Kafka to 2.5.1

* Revert "Bump Kafka to 2.5.1"

This reverts commit 01ab6704206fd23752b5478acaa056693f0291c3.

* Bump to Kafka 2.5.1

* update version number

* Update distribution version

* remove dependency from parent pom

* update parent version in children pom

* Fix wrong k version number

* bump distribution xml version

* bump guava to 24.1.1; change error handling

* use getCause instead of hardcode message

* unwrap execution exception

* centralise exception handling

* refactor exception catching

* fix a wrong if condition

* make exception test more valuable

* address pr comment