Feat/add replica mode argument

[msharma24]

Description

1. Added replica_modeargument to the aws_db_instance so that Oracle RDS instances replicas can use this argument to define whether the replica is in either mounted or open-read-only mode - This enhancement is released in AWS Provider 3.62.0

2. Updated the Complete Oracle EE RDS example engine version from 12 > 19

Motivation and Context

Use replica_mode in Oracle RDS Instances to define whether the replica is in either mounted or open-read-only mode .

Breaking Changes

Does this break backwards compatibility with the current major version? - No

How Has This Been Tested?

• I have tested and validated these changes using one or more of the provided examples/* projects
  Please describe in detail how you tested your changes.
  I have created the Complete Oracle Example TF Template to build a master RDS and then created a replica RDS with master RDS as source DB.
  Include details of your testing environment, and the tests you ran to - Ensure the Replica was created and in 'available` status in AWS console UI.

[antonbabenko]

This issue has been resolved in version 4.0.0 🎉

[github-actions]

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