Added port 6443 during private instance deployment to allow workstations to use kubectl

Package Merge Request

Package Changes

For the default run of k3d-dev.sh, allows port 6443 to the dev's IP so she can run kubectl from her workstation.

Package MR

!2842 (merged)

For Issue

Closes #1537 (closed)

Test Case

I built a cluster from master with ./docs/assets/scripts/developer/k3d-dev.sh -p

➜  bigbang git:(master) echo $KUBECONFIG 
/Users/benfrancis/.kube/Ben.Francis-dev-config
➜  bigbang git:(master) kubectl get nodes                                                          
E0611 20:12:45.306233   13170 memcache.go:265] couldn't get current server API group list: Get "https://172.31.3.212:6443/api?timeout=32s": dial tcp 172.31.3.212:6443: i/o timeout

After making the change, and running the same script:

➜  bigbang git:(1537-unblock-6443-for-workstations-in-k3d-dev) kubectl get nodes                                          
NAME                       STATUS   ROLES                  AGE   VERSION
k3d-k3s-default-agent-2    Ready    <none>                 74s   v1.26.4+k3s1
k3d-k3s-default-agent-0    Ready    <none>                 78s   v1.26.4+k3s1
k3d-k3s-default-agent-1    Ready    <none>                 77s   v1.26.4+k3s1
k3d-k3s-default-server-0   Ready    control-plane,master   81s   v1.26.4+k3s1

Closes #1537 (closed)