fix: allow cancellation of volume expansion when e.Status.CurrentSize…

… is not equal to v.Spec.Size and e.Spec.VolumeSize

When the volume has already been successfully expanded, if the cancellation is issued after
completing the volume expansion, and the spec.size and status.currentSize of the volume and
engine are as follows:

- v.spec.size: 21474836480
- e.spec.size: 21474836480
- e.status.currentSize: 22548578304

The check
```
if e.Spec.VolumeSize == v.Spec.Size {
    return nil
}
```

prevents v.Status.ExpansionRequired from becoming true, which hinders the cancellation
of the expansion.

Longhorn 9466

Signed-off-by: Derek Su <derek.su@suse.com>

controller/volume_controller.go

@@ -2026,7 +2026,7 @@ func (c *VolumeController) reconcileVolumeSize(v *longhorn.Volume, e *longhorn.E
 	if e == nil || rs == nil {
 		return nil
 	}
-	if e.Spec.VolumeSize == v.Spec.Size {
+	if e.Spec.VolumeSize == v.Spec.Size && e.Status.CurrentSize == v.Spec.Size {
 		return nil
 	}