STRATCONN-4121: Customer.io timestamp fix to convert ISO-8601 timestamp to Unix

[kkolhe-twilio]

This pull request is for fixing Customer.io timestamp validation to properly handle high-precision fractional seconds in ISO 8601 date strings.

• Updated the [isIsoDate] function to support fractional seconds with up to 9 digits instead of the previous 6-digit limit
• Improved Regex Pattern: Changed (\.\d{1,6})? to (\.\d{1,9})? to match ISO 8601 standard that allows more than 6 fractional digits

Screen.Recording.2025-08-29.at.11.57.04.AM.mov

Testing improvements:

• Exported [isIsoDate] function and added test coverage for fractional seconds validation from 1-9 digits along with edge cases including invalid dates with more than 9 fractional digits

Testing

Include any additional information about the testing you have completed to
ensure your changes behave as expected. For a speedy review, please check
any of the tasks you completed below during your testing.

• Added unit tests for new functionality
• Tested end-to-end using the local server
• [If destination is already live] Tested for backward compatibility of destination. Note: New required fields are a breaking change.
• [Segmenters] Tested in the staging environment
• [Segmenters] [If applicable for this change] Tested for regression with Hadron.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 79.63%. Comparing base (67a677e) to head (6de7e91).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3212   +/-   ##
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  Coverage   79.62%   79.63%           
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  Files        1177     1177           
  Lines       21703    21704    +1     
  Branches     4220     4221    +1     
=======================================
+ Hits        17282    17283    +1     
  Misses       3679     3679           
  Partials      742      742           

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[rvadera12]

Make sure the tests are passing, before this is ready for release

[joe-ayoub-segment]

Hi @kkolhe-twilio does this change warrant an end to end test before we deploy? Great that the unit tests are passing, but it would be nice to see an end to end test on local using the Actions Tester or on Staging, if possible.

[kkolhe-twilio]

@joe-ayoub-segment I have tested it in staging and in local using actions-tester and it works as expected. I have also added a demo of it working in staging in the PR description.

[joe-ayoub-segment]

Hi @kkolhe-twilio PR deployed