Fixes Warning: Undefined variable $ErrMsg

(cherry picked from commit d2243df299fd75d3418094f3eebefb29666de75a)

Author: pakricard

PcClaimExpensesFromTab.php

@@ -363,6 +363,7 @@
 	//Delete associated taxes
 	$SQL = "DELETE FROM pcashdetailtaxes
 			WHERE pcashdetailtaxes.pccashdetail = '" . $SelectedIndex . "'";
+	$ErrMsg = __('Petty Cash taxes could not be deleted because');
 	$Result = DB_query($SQL, $ErrMsg);
 
 	//Delete expenses record