fix(parser): support camelCase replyTo in SesMailCommonHeaders

[reginaldalfret]

Issue number: closes #8523

Summary

Changes

• Updated SesMailCommonHeaders.reply_to with validation_alias=AliasChoices("replyTo", "reply-to", "reply_to") and serialization_alias="replyTo", ensuring standard SES notifications parse correctly while retaining backward compatibility for any existing usage.
• Added comprehensive unit tests in tests/unit/parser/_pydantic/test_ses.py covering standard camelCase SES payloads, hyphenated payloads, and keyword argument instantiation.

User experience

In SES email receiving notifications, the mail.commonHeaders object provides the Reply-To addresses under the camelCase key replyTo (matching the SES API specification and SESMail.reply_to in aws_lambda_powertools.utilities.data_classes.ses_event).

Previously, SesMailCommonHeaders in aws_lambda_powertools.utilities.parser.models.ses declared the alias strictly as "reply-to". Consequently, whenever SES payloads containing commonHeaders.replyTo were parsed with SesModel, the reply_to field was ignored and evaluated to None.

With this fix, SES event payloads with commonHeaders.replyTo correctly populate reply_to.

Verification

• Ran pytest tests/unit/parser/_pydantic/test_ses.py: 2 passed cleanly.

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[boring-cyborg]

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.96%. Comparing base (2f58434) to head (45a1f0f).

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #8542   +/-   ##
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  Coverage    96.96%   96.96%           
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  Files          317      317           
  Lines        15932    15932           
  Branches      1403     1403           
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  Hits         15448    15448           
  Misses         349      349           
  Partials       135      135           

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[leandrodamascena]

Thanks @reginaldalfret! I was able to reproduce the bug and confirm the fix. I pushed a small commit to your branch applying ruff format to the test file so the quality check passes, nothing else changed.

Thanks also to @LuisFigueroaG for the detailed report. Approving!

[boring-cyborg]

Awesome work, congrats on your first merged pull request and thank you for helping improve everyone's experience!

[powertools-for-aws-oss-automation]

Awesome work, congrats on your first merged pull request and thank you for helping improve everyone's experience!