(CAT-2413) Defaults puppetcore agent version to newest if none given

When puppetcore is selected without a specified version, this change defaults to the latest 8.x version available.

This prevents errors caused by the download site requiring a version parameter.

Relates to CAT-2413

Author: david22swan

tasks/install_powershell.ps1

@@ -120,6 +120,16 @@ if (($collection -like '*nightly*') -And -Not ($PSBoundParameters.ContainsKey('w
   $windows_source = 'https://nightlies.puppet.com/downloads'
 } elseif (($collection -like '*puppetcore*') -And -Not ($PSBoundParameters.ContainsKey('windows_source'))) {
   $windows_source = 'https://artifacts-puppetcore.puppet.com/v1/download'
+  
+  # Puppetcore requires a version to be specified, so we will use the latest version if not specified.
+  # Or if the version is set to "latest".
+  if ($version -eq "" || !$version || $version -eq "latest") {
+    $version = ((Invoke-WebRequest -Uri "https://forgeapi.puppet.com/private/versions/puppet-agent" -UseBasicParsing).Content
+      | ConvertFrom-Json).PSObject.Properties.Name
+      | Where-Object { $_ -like "8.*" }
+      | Sort-Object { [Version]$_ }
+      | Select-Object -Last 1
+  }
 }
 
 if ($absolute_source) {
@@ -131,6 +141,7 @@ if ($absolute_source) {
     } else {
         $dev = ''
     }
+  
     $msi_source = "${windows_source}?type=native&version=${version}&os_name=windows&os_version=${major_os_version}&os_arch=${arch}&fips=${fips}${dev}"
 } else {
     $msi_source = "$windows_source/windows/${collection}/${msi_name}"

tasks/install_shell.sh

@@ -152,6 +152,12 @@ if [ -n "$PT_mac_source" ]; then
   mac_source=$PT_mac_source
 elif [[ "$collection" == "puppetcore"* ]]; then
   mac_source='https://artifacts-puppetcore.puppet.com/v1/download'
+  # Puppetcore requires a version to be specified, so we will use the latest version if not specified.
+  # Or if the version is set to "latest".
+  if ($version -eq "" || !$version || $version -eq "latest") {
+    $version = curl -sL https://forgeapi.puppet.com/private/versions/puppet-agent
+      | jq -r ' keys_unsorted | map(select(startswith("8.")))| max_by( split(".") | map(tonumber) )'
+  }
 elif [ "$nightly" = true ]; then
   mac_source='http://nightlies.puppet.com/downloads'
 else