feat(parameters): migrate AppConfig to new APIs due to API deprecation

[leandrodamascena]

Issue number: #1506

Summary

Changes

Due to Deprecation of the AppConfig API, we needed to change the SDK client to call the new APIs.

We had a long discussion in this issue #1506 before applying these changes.

User experience

No changes are required to Lambda functions that use Feature Flags and AppConfig Parameter utility, but users must add appconfig:GetLatestConfiguration and appconfig:StartConfigurationSession IAM permissions for this to work in their Lambdas.

Checklist

If your change doesn't seem to apply, please leave them unchecked.

• [x ] Meet tenets criteria
• [x ] I have performed a self-review of this change
• [x ] Changes have been tested
• [x ] Changes are documented
• [x ] PR title follows conventional commit semantics

Is this a breaking change?

RFC issue number:

Checklist:

• Migration process documented
• Implement warnings (if it can live side by side)

Acknowledgment

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

Disclaimer: We value your time and bandwidth. As such, any pull requests created on non-triaged issues might not be successful.

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View rendered docs/upgrade.md

[codecov-commenter]

Codecov Report

Base: 99.42% // Head: 99.38% // Decreases project coverage by -0.03% ⚠️

Coverage data is based on head (f3abe06) compared to base (fd7c235).
Patch coverage: 87.50% of modified lines in pull request are covered.

Additional details and impacted files

@@            Coverage Diff             @@
##               v2    #1553      +/-   ##
==========================================
- Coverage   99.42%   99.38%   -0.04%     
==========================================
  Files         125      125              
  Lines        5726     5731       +5     
  Branches      357      359       +2     
==========================================
+ Hits         5693     5696       +3     
  Misses         18       18              
- Partials       15       17       +2     

Impacted Files	Coverage Δ
...ambda_powertools/utilities/parameters/appconfig.py	94.28% <86.66%> (-5.72%)	⬇️
aws_lambda_powertools/utilities/parameters/base.py	100.00% <100.00%> (ø)

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[leandrodamascena]

Giving feedback here.
I need to add more information in the doc files, but we hope to review and merge this PR later this week.

[heitorlessa]

Looking into this now [apologies for the delay, re:Invent deadlines are tighter this year]

[heitorlessa]

Thanks a lot @leandrodamascena for working on this, truly!

I've made some wording suggestions, and some concerns on E2E tests:

• Separate SSM from this PR for a clean cut and revert if we need
• Some resources have names hardcoded, this might bite us back in parallel testing or network failures (e.g., SSM will fail subsequent stack if a param name already exists)

[leandrodamascena]

Thanks a lot @leandrodamascena for working on this, truly!

I've made some wording suggestions, and some concerns on E2E tests:

• Separate SSM from this PR for a clean cut and revert if we need
• Some resources have names hardcoded, this might bite us back in parallel testing or network failures (e.g., SSM will fail subsequent stack if a param name already exists)

Heiiiiii @heitorlessa! I've addressed all the feedback and I think we're ready to merge.

Thank you so much for reviewing this, every time you give me WONDERFUL feedback to think about UX and see beyond the code. ❤️

[heitorlessa]

THANK YOU! I'm glad we're completing this and we're ready for the grooming part before launching V2 now.

Last suggestions I'm committing myself is on being more explicit on AppConfig Config/Env Name and Description. If a network split happens, this will leave dangling resources making it difficult to trace back to what they are for (appe2e vs powertools-e2e-x).