text2vec-aws module doesn't support temporary credentials

[bbeaumatin]

Describe your feature request

Problem:
At the moment the module can only take permanent credentials "access key" and "secret key".

Solution:
A common way of consuming AWS APIs also involves temporary credentials : https://docs.aws.amazon.com/IAM/latest/UserGuide/security-creds.html#sec-access-keys-and-secret-access-keys

Basically it would need to receive a "session token" additionally to the access key and secret key, in order to be able to pass those temp credentials.

Also those credentials can expire, so it means the module could either use the go SDK of aws to ensure the logic of the credentials provider is the same as usual other uses of AWS sdks (there is a logical chain of keys providers), or otherwise document that the app instantiating the aws client takes the responsibility of recreating the client upon expiration of the keys (which might not be straightforward in some scenarios)

Let me know if it needs more meaningful information.

Code of Conduct

• I have read and agree to the Weaviate's Contributor Guide and Code of Conduct