Remove log redirect, add quick start buildkite-agent

Author: Chloe Hutchinson

packer/windows/conf/bin/bk-install-elastic-stack.ps1

@@ -172,7 +172,7 @@ nssm set buildkite-agent AppExit Default Restart
 If ($lastexitcode -ne 0) { Exit $lastexitcode }
 nssm set buildkite-agent AppRestartDelay 5000
 If ($lastexitcode -ne 0) { Exit $lastexitcode }
-nssm set buildkite-agent AppEvents Exit/Post "powershell C:\buildkite-agent\bin\terminate-instance.ps1 3>&1 2>&1 > C:\buildkite-agent\buildkite-agent.log"
+nssm set buildkite-agent AppEvents Exit/Post "powershell C:\buildkite-agent\bin\terminate-instance.ps1"
 If ($lastexitcode -ne 0) { Exit $lastexitcode }
 
 Restart-Service buildkite-agent

packer/windows/conf/buildkite-agent/scripts/terminate-instance.ps1

@@ -13,4 +13,5 @@ if ($lastexitcode -eq 0) { # If autoscaling request was successful, we will term
 }
 else {
   Write-Output "terminate-instance: ASG could not decrement (we're already at minSize)"
+  nssm start buildkite-agent
 }