Refactored iap code

[jawad-khan]

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• I have checked the branch to which I would like to merge.

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This repository is deprecated and in maintainence-only operation while we work on a replacement, please see this announcement for more information.

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Anyone internally merging to this repository is expected to release and monitor their changes; if you are not able to do this DO NOT MERGE, please coordinate with someone who can to ensure that the changes are released.

Required Testing

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  (^ We can remove that manual check once REV-2624 is done and the corresponding e2e test runs again)

Description

Refactored iap code, improved test coverage and removed deprictaed params.

Supporting information

Here is the JIRA TICKET for refactoring.

Testing instructions

Please provide detailed step-by-step instructions for testing this change; how did YOU test this change?

Other information

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• Does this change depend on other changes elsewhere?
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