Add clarification about AWS Connection behaviour

[Taragolis]

It is not uncommon when user tried to use Amazon provider for interact with AWS API compatible services (MinIO or others).
Even if we do not officially support them better provide additional information how to correctly understand AWS Connection testing.

In additional I add information about missing connections and deprecated AwsBaseHook behaviour.

Feel free to suggest any improvements in text

[eladkal]

Do we have a way to link this doc to the test button of Amazon provider?

[o-nikolas]

Thanks for updating these docs! Your efforts on improving the boto3 credential management and related documentation is very much appreciated :)

[ferruzzi]

Good clarifications, thanks

[Taragolis]

Do we have a way to link this doc to the test button of Amazon provider?

I tried to find this way in last summer but better that I could find it was placeholder to description unfortunetly it is useless because it quite difficult to copy this value without DevTools.

I've also tried custom fields and put it in description, but without any luck to make this URL clickable.

I think that probably there is exists better way to solve a lot of problem with Connections, maybe we should make it pluggable and decompose it out of the Hooks, hooks still should use them but as separate object which initialise everything required behind the hook itself, and make it more extensible, self documented and provide better custom fields support rather than now. But it just my thoughts, I tried to find a more reliable way since I try to implement ECR login to docker hook.