Extend AWS default credential chain instead of replacing it

[exalate-issue-sync]

A user reported credentials access issue when running on AWS EC2 on Kubernetes: [https://groups.google.com/g/h2ostream/c/R3LXW8ybBPM/m/fuI_NlkvAAAJ|https://groups.google.com/g/h2ostream/c/R3LXW8ybBPM/m/fuI_NlkvAAAJ|smart-link]

The user makes an interesting point that aws cli work when they log in the running instance.

Our code modifies the credential chain that AWS SDK provides - it does that in a way that instead of extending it replaces it as a whole, this means any improvement/fixes in the default chain are not propagated to H2O.

The goal of this Jira is to re-use the default chain and extend it with H2O’s specific extensions.

[h2o-ops-ro]

JIRA Issue Details

Jira Issue: PUBDEV-8557
Assignee: Michal Kurka
Reporter: Michal Kurka
State: Resolved
Fix Version: 3.36.0.3
Attachments: N/A
Development PRs: Available

[h2o-ops-ro]

Linked PRs from JIRA

#6047