update to use atera api to get customer host url

Install-LiquidFilesOutlookAgent.ps1

@@ -1,8 +1,20 @@
 ## Path to the MSI installer
 $MSIURL = 'https://dev.emberkom.com/emberkom/management-scripts/raw/branch/master/resources/LiquidFiles_Admin_2.0.129.msi'
 
+Install-PSAteraModule
+Import-Module -Name PSAtera
+
+## Get LF host URL from Atera
+Try {
+    LogMsg "Getting LiquidFiles host URL from Atera API"
+    Set-AteraAPIKey -APIKey $AteraAPIKey
+    $AteraAgent = Get-AteraAgent
+    $LFHost = $(Get-AteraCustomValue -ObjectType Customer -ObjectId $AteraAgent.CustomerID -FieldName 'LiquidFiles Host URL').ValueAsString
+}
+Catch { LogErr $_.Exception.Message }
+
 ## Set installer args
-If ( $LFHost ) {
+If (-not [string]::IsNullOrEmpty($LFHost) ) {
     LogMsg "LiquidFiles target server: ${LFHost}"
     $INSTALLER_ARGS = "REGKEYSCRIPT=""BaseUrl=${LFHost};"""
 }