Does the daemon support SSO?

We are trying to use the daemon with SSO for local testing and are facing some issues.

```
2021-07-15T17:05:27-06:00 [Info] Initializing AWS X-Ray daemon 3.3.2
2021-07-15T17:05:27-06:00 [Info] Using buffer memory limit of 163 MB
2021-07-15T17:05:27-06:00 [Info] 2608 segment buffers allocated
2021-07-15T17:05:27-06:00 [Info] Using region: us-west-2
2021-07-15T17:05:27-06:00 [Info] HTTP Proxy server using X-Ray Endpoint : https://xray.us-west-2.amazonaws.com
2021-07-15T17:05:27-06:00 [Info] Starting proxy http server on 127.0.0.1:2000
2021-07-15T17:07:39-06:00 [Error] Unable to sign request: NoCredentialProviders: no valid providers in chain. Deprecated.
```

From what I understand,[ the go sdk supports SSO](https://docs.aws.amazon.com/sdk-for-go/api/aws/credentials/ssocreds/) but does the aws-xray-daemon implement this functionality?

My credentials file looks like

```
[profile ]
sso_start_url =
sso_region = us-west-2
sso_account_id =
sso_role_name =
region =
```

And we are invoking the daemon with `./xray_mac -o -n us-west-2`

Start by tracing how ./xray_mac -o -n us-west-2 obtains AWS credentials and compare that behavior with the linked Go SDK SSO support, using the supplied credentials profile and NoCredentialProviders error as the reproduction. Done means establishing whether this profile is supported and, if not, defining the required SSO behavior and a regression test.

Written by the indexing model from the issue text.