Return Error on Conflicting Credential Configuration

**Is your feature request related to a problem or challenge? Please describe what you are trying to do.**

Comment from @alamb on https://github.com/apache/arrow-rs/pull/4235/files#r1196996290 suggested erroring if an object_store is constructed with multiple conflicting credentials. The current behaviour of not returning an error is consistent with the behaviour of tools like AWS SDK, but may not be desirable in all cases. Creating an issue to solicit thoughts.

**Describe the solution you'd like**

I'm honestly not sure, but I think we should probably either do nothing or return an error.

**Describe alternatives you've considered**

**Additional context**

No file, test, or entry point is named. Read the discussion linked from pull request 4235 and inspect how object_store handles multiple credentials; completion is not defined because the issue leaves the choice between preserving current behavior and returning an error unresolved.

Written by the indexing model from the issue text.