[REF] Replace long if block with early return

[eileenmcnaughton]

Overview

All the functional code in this function is within an if - this removes that & uses an early return if not instead

Before

if ($x_subscription_id) {
 .. do the stuff
}

After

if (!$x_subscription_id) {
  return;
}
 .. do the stuff

Technical Details

Comments

[civibot]

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