Add support for role arn for aws creds in storage transfer job operators

[wlinamchurch]

closes: #35271
related: Attempt to fix tests and checks from #35292

This PR adds support to use role arn's for AWS credentials in storage transfer jobs. All of the substantive code changes were made in #35292.

My additional contributions were to get the tests to pass and pre-commit checks to pass.

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[boring-cyborg]

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[wlinamchurch]

@Taragolis apologies if this is not the correct way to do this but tagging you since you looked at #35292 previously.

[wlinamchurch]

@Taragolis - pinging again following the directions of "be persistent". Again, apologies if this is not the correct procedure.

[ferruzzi]

I don't know google provider very well so there may be something I'm missing, but the code LGTM. If those unit tests are passing and the CI goes green, I think it's good to merge.

[wlinamchurch]

Thanks @ferruzzi!

[ferruzzi]

@wlinamchurch You still need one more approval, perhaps drop a message in the slack #contributors channel asking for another set of eyes.

[wlinamchurch]

Thanks @Taragolis!

[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.

[ferruzzi]

Congrats! Thanks for your contribution and your patience!