ci: use wait-for-it instead of just waiting for 10s

Signed-off-by: Vincent Fu <vincent.fu@samsung.com>

.github/actions/start-vm/action.yml

@@ -25,6 +25,9 @@ inputs:
 runs:
  using: "composite"
  steps:
+ - name: install wait-for-it
+ run: sudo apt install -y wait-for-it
+ shell: bash
  - name: Start VM in background
  run: |
  ${{ inputs.qemu }} \
@@ -43,7 +46,7 @@ runs:
  env:
  SSHCMD: ssh root@localhost -p ${{ inputs.ssh_fwd_port }}
  - name: Wait for VM to boot
- run: sleep 10
+ run: wait-for-it localhost:${{ inputs.ssh_fwd_port }} -t 15
  shell: bash
  - name: Add guest host key to known_hosts
  run: |