fix(ibm): Fix get_instance (#488)

## Description

IBM library get_instance returns a DetailedResponse object, not an
instance dict directly. This fix gets the instance dict result from that
object before passing it to from_existing.


## Additional Context and Relevant Issues

Previous behavior throws a TypeError

```
  File "/home/shammer/Canonical/git/tools/ubuntu-old-fashioned/scripts/ubuntu-bartender/ibm-provider.py", line 34, in <module>
    delete(args.id)
  File "/home/shammer/Canonical/git/tools/ubuntu-old-fashioned/scripts/ubuntu-bartender/ibm-provider.py", line 22, in delete
    instance = ibm.get_instance(instance_id)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/shammer/ubuntu-bartender-multipass.pedbPM1KcM/.venv/lib/python3.12/site-packages/pycloudlib/ibm/cloud.py", line 230, in get_instance
    return IBMInstance.find_existing(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/shammer/ubuntu-bartender-multipass.pedbPM1KcM/.venv/lib/python3.12/site-packages/pycloudlib/ibm/instance.py", line 702, in find_existing
    return cls.from_existing(
           ^^^^^^^^^^^^^^^^^^
  File "/home/shammer/ubuntu-bartender-multipass.pedbPM1KcM/.venv/lib/python3.12/site-packages/pycloudlib/ibm/instance.py", line 675, in from_existing
    floating_ip = kwargs.pop("floating_ip", None) or cls._discover_floating_ip(client, instance)
                                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/shammer/ubuntu-bartender-multipass.pedbPM1KcM/.venv/lib/python3.12/site-packages/pycloudlib/ibm/instance.py", line 773, in _discover_floating_ip
    nic_id = instance["primary_network_interface"]["id"]
             ~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: 'DetailedResponse' object is not subscriptable
```


## Test Steps

Create an instance and perform a get_instance

```python
import pycloudlib

ibm = pycloudlib.IBM("test")
imge = ibm.daily_image(release="noble")
instance = ibm.launch(image_id=daily, instance_type="bx3d-2x10", name="test")
id = instance._instance["id"]
instance_find = ibm.get_instance(id)  # previously would throw an exception here
```

Author: hammerstefan

VERSION

@@ -1 +1 @@
-1!10.13.0
+1!10.13.1

pycloudlib/ibm/instance.py

@@ -692,9 +692,11 @@ def find_existing(
         **kwargs,
     ) -> "IBMInstance":
         """Find an instance by ID."""
-        instance = _IBMInstanceType.VSI.get_instance(client, instance_id)
+        response = _IBMInstanceType.VSI.get_instance(client, instance_id)
+        instance = response.result
         if not instance:
-            instance = _IBMInstanceType.BARE_METAL_SERVER.get_instance(client, instance_id)
+            response = _IBMInstanceType.BARE_METAL_SERVER.get_instance(client, instance_id)
+            instance = response.result
 
         if not instance:
             raise IBMException(f"Instance not found: {instance_id}")