[UI] Add Object Storage Fails using GET Instead of POST to Backend

### problem

When trying to Add Object Storage, the UI fails because it sends the payload over GET when it expects POST.

I confirmed that the backend works properly when the request is sent using CloudMonkey.

As I've pointed out before, the ACS UI overuses GET, including for operations where sensitive data is passed in the URL. In this case it happens to break the UI, but we should probably review this behavior more holistically.

### versions

Non-Prod deployment of ACS 4.22.0.1
The backend S3-compatible object storage type is MinIO.

### The steps to reproduce the bug

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### What to do about it?

_No response_

Start by tracing the UI's Add Object Storage request and compare its method and payload with the working CloudMonkey request to the backend. Done means the UI sends the operation as POST and successfully adds MinIO object storage; the linked pull request indicates work is already underway.

Written by the indexing model from the issue text.