Refactor example 9 to use thumbprint variable

Updated example 9 to use a variable for the certificate thumbprint.

Author: dangshubham

sharepoint/sharepoint-ps/Microsoft.Online.SharePoint.PowerShell/Connect-SPOService.md

@@ -127,7 +127,8 @@ Connect to the SharePoint Online service using an app identity and a certificate
 ### EXAMPLE 9
 
 ```powershell
-$cert = Get-ChildItem Cert:\LocalMachine\My\$CertThumbprint
+$thumbprint = "<3F2A5C9D4E7B8A1234567890ABCDEF1234567890>"
+$cert = Get-ChildItem Cert:\LocalMachine\My\$thumbprint "
 Connect-SPOService -Url https://contoso-admin.sharepoint.com -ClientId 00000000-0000-0000-0000-000000000000 -Tenant 11111111-1111-1111-1111-111111111111 -Certificate $cert
 ```
 Connect to the SharePoint Online service using an app identity and a certificate object.