Agent: Add OTP fetching to the island api client

[VakarisZ]

What does this PR do?

Fixes a task in #3077

Add any further explanations here.

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• Was the CHANGELOG.md updated to reflect the changes?
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Testing Checklist

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  Tested by running unit tests

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[codecov]

Codecov Report

Patch coverage has no change and project coverage change: +0.01 🎉

Comparison is base (cef8508) 67.64% compared to head (79433da) 67.65%.

❗ Current head 79433da differs from pull request most recent head 48c5393. Consider uploading reports for the commit 48c5393 to get more accurate results

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #3101      +/-   ##
===========================================
+ Coverage    67.64%   67.65%   +0.01%     
===========================================
  Files          445      445              
  Lines        12760    12764       +4     
===========================================
+ Hits          8632     8636       +4     
  Misses        4128     4128              

see 1 file with indirect coverage changes

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[cakekoa]

Is the HTTPIslandAPIClient going handle all authentication and therefore we don't need to expose those methods in the IIslandAPIClient?

[shreyamalviya]

The method needs to be added to the IIslandAPIClient too.