Allow SSEC bucket decryption in s3 integ tests

[arandito]

Explicitly re-enable SSE-C on S3 integration test buckets after creation so SSE-C tests continue to pass after the April 2026 default bucket-setting rollout.

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.42%. Comparing base (c4681b5) to head (8ca8f93).
⚠️ Report is 256 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #10203      +/-   ##
===========================================
+ Coverage    93.39%   93.42%   +0.03%     
===========================================
  Files          210      210              
  Lines        17052    17229     +177     
===========================================
+ Hits         15925    16097     +172     
- Misses        1127     1132       +5     

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