[CHA-RL1] Implement Room ATTACH operation

[sacOO7]

• Implement all spec items that come under CHA-RL1.
• Implement related integration tests.
• Split from Chat Room: implement room lifecycle spec #6

┆Issue is synchronized with this Jira Task by Unito

[sacOO7]

• Implemented as a part of [ECO-5009][CHA-RL1] Room ATTACH  #27
• Omitted CHA-RL1i ( make sure room is released before created), this will be covered as a part of Room release operation. Also, there's a discussion about changes in room lifecycle spec. So, related specs might change depending on the same.
• Unit tests will be covered by [ECO-5009][CHA-RL1] RoomLifecycle ATTACH tests #37

[sacOO7]

Two PRs marked as ready for review

• Room ATTACH with internal RETRY -> [ECO-5009][CHA-RL1] Room ATTACH with retry #33
• Room ATTACH unit tests -> [ECO-5009][CHA-RL1] RoomLifecycle ATTACH tests #37