Fix wrong line numbers by not trimming the start of expressions

We still trim the end because else `Tokenizer` crashes...
But trimming the end doesn't matter because there's it doesn't affect anything.

src/main/java/carpet/script/Expression.java

@@ -748,7 +748,7 @@ public class Expression
      */
     public Expression(String expression)
     {
-        this.expression = expression.trim().replaceAll("\\r\\n?", "\n").replaceAll("\\t","   ");
+        this.expression = expression.stripTrailing().replaceAll("\\r\\n?", "\n").replaceAll("\\t","   ");
         Operators.apply(this);
         ControlFlow.apply(this);
         Functions.apply(this);