- added `getCredentials` callback in `S3Config`
- simplified signer test util ( `sigv4-signer.js` ) and moved to
`src/signer.ts`
- all tests run in a new non root minio user ( required for sts ) ,
which gets created before the tests start see `tests/s3-client/setup.js`
- tests added for sts , using `@aws-sdk/client-sts` for getting creds.
- credential caching inspired from the current implementation in
`@aws-s3` plugin , see `#getTemporarySecurityCredentials` inside
`@uppy/aws-s3/src/index.ts`
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Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>