build(deps-dev): bump aws-lambda-powertools from 3.20.0 to 3.21.0

Bumps [aws-lambda-powertools](https://github.com/aws-powertools/powertools-lambda-python) from 3.20.0 to 3.21.0.
- [Release notes](https://github.com/aws-powertools/powertools-lambda-python/releases)
- [Changelog](https://github.com/aws-powertools/powertools-lambda-python/blob/develop/CHANGELOG.md)
- [Commits](aws-powertools/powertools-lambda-python@v3.20.0...v3.21.0)

---
updated-dependencies:
- dependency-name: aws-lambda-powertools
  dependency-version: 3.21.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

poetry.lock

@@ -33,7 +33,7 @@ boto3 = "^1.40.40"
 moto = "^5.1.10"
 pyparsing = "^3.2.4"
 types-python-dateutil = "^2.9.0.20250822"
-aws-lambda-powertools = "^3.20.0"
+aws-lambda-powertools = "^3.21.0"
 
 
 [tool.poetry.group.local.dependencies]