fix: use the node name instead of the hostname to build the injector …

…pod (#2119)

## Description

This sets the injector pod to use the node name instead of the hostname
to more properly select the node it should run on.

## Related Issue

Fixes #2110

## Type of change

- [X] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Other (security config, docs update, etc)

## Checklist before merging

- [ ] Test, docs, adr added or updated as needed
- [x] [Contributor Guide
Steps](https://github.com/defenseunicorns/zarf/blob/main/CONTRIBUTING.md#developer-workflow)
followed

src/internal/cluster/injector.go

@@ -304,7 +304,7 @@ func (c *Cluster) buildInjectionPod(node, image string, payloadConfigmaps []stri
 	pod.Labels[agentLabel] = "ignore"
 
 	// Bind the pod to the node the image was found on
-	pod.Spec.NodeSelector = map[string]string{"kubernetes.io/hostname": node}
+	pod.Spec.NodeName = node
 
 	// Do not try to restart the pod as it will be deleted/re-created instead
 	pod.Spec.RestartPolicy = corev1.RestartPolicyNever