vm_darwin.go: remove filesToRemove

`filesToRemove` was not effective until this PR, because above `defer`:
```golang
	filesToRemove := make(map[string]struct{})
	defer func() {
		for f := range filesToRemove {
			_ = os.RemoveAll(f)
		}
	}()
```
has passed before `filesToRemove[pidFile] = struct{}{}` has effect.
Because I changed to wait `waitSSHLocalPortAccessible`, above `defer` changed to remove `pidFile`.
That’s why test fails with:
https://github.com/lima-vm/lima/actions/runs/17849303510/job/50754678943?pr=3979#step:9:165
> time="2025-09-19T05:30:22Z" level=fatal msg="expected status \"Running\", got \"Broken\" (maybe use `limactl stop -f`?)"

I think `filesToRemove` is not required.
I'll remove them.

Signed-off-by: Norio Nomura <[email protected]>

Author: norio-nomura

pkg/driver/vz/vm_darwin.go

@@ -72,12 +72,6 @@ func startVM(ctx context.Context, inst *limatype.Instance, sshLocalPort int) (*v
 
 	errCh := make(chan error)
 
-	filesToRemove := make(map[string]struct{})
-	defer func() {
-		for f := range filesToRemove {
-			_ = os.RemoveAll(f)
-		}
-	}()
 	waitSSHLocalPortAccessible := make(chan struct{})
 	defer close(waitSSHLocalPortAccessible)
 	go func() {
@@ -107,7 +101,6 @@ func startVM(ctx context.Context, inst *limatype.Instance, sshLocalPort int) (*v
 						logrus.Errorf("error writing to pid fil %q", pidFile)
 						errCh <- err
 					}
-					filesToRemove[pidFile] = struct{}{}
 					logrus.Info("[VZ] - vm state change: running")
 
 					usernetSSHLocalPort := sshLocalPort