[CDF-25601] 🤩Replace client (#1983)

# Description

This replaces the `HTTPBatchProcessor` with the `HTTPClient` which is
first step towards removing it from the code base.


## Changelog

- [x] Patch
- [ ] Skip

## cdf

### Fixed

- [alpha] When running `cdf purge instances`, Toolkit now handles 408
responses from the API by splitting the request into multiple requests.
 
## templates

No changes.
