Add ability to use AWS SSO profile as a credential provider

[konidev20]

I have a feature request, I want the ability to use AWS SSO profile stored in .aws/sso/cache to retrieve temporary access keys and session tokens to my S3 bucket.

Here is the corresponding AWS SDK SSO credential provider in golang for reference.
https://pkg.go.dev/github.com/aws/aws-sdk-go-v2/credentials/ssocreds

[harshavardhana]

Please test #1911

[fdw]

I'd like to test it in restic, but I have no idea how to do that. But looking at the code, it seems to do the right things.

[konidev20]

@fdw I can help you with that. I can take a look at this next weekend and help you out.

[fdw]

Have you had a chance yet to implement it?

[konidev20]

Hey @fdw,
I need some more time to look in to this.

[fdw]

Reporting back after trying out @konidev20's build of restic: It doesn't seem to work for me. I always get some kind of client.BucketExists: 301 Moved Permanently that suggest some permissions problem. I'm also not asked to login.
Hope that helps :)