feat: support secrets in render task definition

[yehudacohen]

Issue #, if available:
#20
Description of changes:
Add ability to add secrets to task definition. There is already a pull request here #143 which tries to do this, but it isn't backward compatible. This pull request is. It also doesn't add tests which this PR does.

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[kroehre]

👍 we'd love to use this feature. What's blocking?

[cairesvs]

Hi 👋 Any updates about when this will be merged? I think it's a needed feature 🙏

[canhassancode]

Hi there, any update on this?

[amazreech]

Hi @yehudacohen, thank you so much for your contribution. Apologies on the delay.
We will be working on reviewing Pull Requests on the repository. In the mean time please ensure that below steps, if not already done, are taken care of in your PR:

1. Verify if PR follows semantic pull request conventions.

2. Please be sure to run npm run package command to update dist/ folder with latest dependencies.

3. Resolve merge conflicts on the PR if any.