[receiver/vcenter] Print the correct error message if VM fetch fails (o…

…pen-telemetry#15685)

Print the correct error message if VM fetch fails

.chloggen/vcenter-err.yaml

@@ -0,0 +1,16 @@
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: 'bug_fix'
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: vcenterreceiver
+
+# A brief description of the change. Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Print the correct error message if VM fetch fails.
+
+# One or more tracking issues related to the change
+issues: [15682]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:

receiver/vcenterreceiver/client.go

@@ -101,7 +101,7 @@ func (vc *vcenterClient) Clusters(ctx context.Context, datacenter *object.Datace
  vc.finder = vc.finder.SetDatacenter(datacenter)
  clusters, err := vc.finder.ClusterComputeResourceList(ctx, "*")
  if err != nil {
- return []*object.ClusterComputeResource{}, err
+ return []*object.ClusterComputeResource{}, fmt.Errorf("unable to get cluster lists: %w", err)
  }
  return clusters, nil
 }
@@ -118,7 +118,7 @@ func (vc *vcenterClient) ResourcePools(ctx context.Context) ([]*object.ResourceP
 func (vc *vcenterClient) VMs(ctx context.Context) ([]*object.VirtualMachine, error) {
  vms, err := vc.finder.VirtualMachineList(ctx, "*")
  if err != nil {
- return nil, fmt.Errorf("unable to retrieve resource pools: %w", err)
+ return nil, fmt.Errorf("unable to retrieve vms: %w", err)
  }
  return vms, err
 }