chore(deps): update akhileshns/heroku-deploy action to v3.13.15

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
akhileshns/heroku-deploy	action	minor	v3.12.14 -> v3.13.15

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Release Notes

akhileshns/heroku-deploy (akhileshns/heroku-deploy)

v3.13.15

Compare Source

Updated node version to "node20" (as "node18" is not supported by GitHub Actions)

v3.13.14

Compare Source

Updated node version from 16 to 18 (as 16 is causing problems due to deprecation)

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• If you want to rebase/retry this PR, check this box

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 92.50%. Comparing base (f257774) to head (1c15232).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #613   +/-   ##
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  Coverage   92.50%   92.50%           
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  Files           4        4           
  Lines          80       80           
  Branches       23       23           
=======================================
  Hits           74       74           
  Misses          5        5           
  Partials        1        1