Why automator's component "Get Selected Finder Items" duplicates path of selected file?
When run from the Automator app it needs the Get Selected Finder Items action, however when run as a Quick Action from Finder it isn't needed as the selected files in Finder are passed to the Quick Action.
You need to remove or disable the Get Selected Finder Items action to have the duplication stopped when run as a Quick Action.
To disable an action, check the [√] Ignore this action's input under the action's Options.