autoload-credentials doesn't import aws credential in env var

[Natasha Ho]

juju version:
It's reproducible on 2.9.31-ubuntu-amd64
It's unclear which version of juju where this bug is introduced.

What cloud?
AWS. I did not test on other clouds

Steps:
```
export AWS_ACCESS_KEY_ID=test-access=id
export AWS_SECRET_ACCESS_KEY=test-secret-access-key
juju autoload-credentials --client aws
```

Observed output:
Looking for cloud and credential information on local client...
No cloud credentials found.

[Ian Booth (wallyworld)]

It looks like juju only checks environment variables if there are no credentials defined in ~/.aws/credentials

This behaviour is not new. Whether juju should always look for both env and .aws credentials is another question. I suspect the thinking was that if there were .aws credentials, that should be the definitive source of truth.

Can you confirm that if you rename ~/.aws it now works? It may be we just need to document this better.

[Natasha Ho (natashaho)]

I don't have ~/.aws on my machine

[Launchpad Janitor (janitor)]

[Expired for juju because there has been no activity for 60 days.]