Internal API's used by ServiceControl for accessing management API not working for servers are using a virtual path

[ramonsmits]

Symptoms

ServiceControl usage reporting not working. The logs showing 404's.

Who's affected

ServiceControl users that want to configure usage reporting for a broker that uses a virtual path.

Root cause

The BasePath on the HttpClient was ignored because the url was prefixed with a /.

Confirmed workarounds

Original bug report

### Describe the bug

Description

The management api is by default hosted at /api/, but a RabbitMQ server can be configured to use a path prefix like /my-prefix to the api is accessible at /my-prefix/api.

Expected behavior

When a RabbitMQ instance that uses a path prefix is configured configuring the topology on the broker should not fail.

Actual behavior

Creating bindings and querying queue and binding information fails.

Versions

• 10.1

Steps to reproduce

1. Setup a RabbitMQ server with a path prefix
2. Configure the endpoint to use this path prefix
3. Launch it and have the installers run

Relevant log output

Additional Information

No response