docs(general): Sample code errors - Pass by Value and Pass by Reference

YoYoGames/GameMaker-Bugs#9226

Fixed incorrect variable names passed to the functions in the code sample

Manual/contents/GameMaker_Language/GML_Overview/Values_And_References.htm

@@ -80,11 +80,11 @@ <h2 id="pass_by_value_and_pass_by_reference">Pass by Value and Pass by Reference
     }<br />
     <br />
     var _val_orig = 48593;<br />
-    try_to_modify_value(_val, 75);<br />
+    try_to_modify_value(_val_orig, 75);<br />
     show_debug_message(_val_orig);<br />
     <br />
     var _array_orig = [1, 2, 3];<br />
-    try_to_modify_array(_array, 100);<br />
+    try_to_modify_array(_array_orig, 100);<br />
     show_debug_message(_array_orig);
   </p>
   <p>In the call to <span class="inline3_func">try_to_modify_value()</span>, the value stored in <span class="inline2">_val_orig</span> is assigned to the function parameter <span class="inline2">_value</span>. Since this value is 48593, i.e. of type <span data-keyref="Type_Real"><a href="Data_Types.htm" target="_blank">Real</a></span>, it is copied. The new value 75 is assigned to <span class="inline2">_value</span>, which goes &quot;out of scope&quot; after the function finishes. <span class="inline2">_val_orig</span> isn&#39;t changed at all and still holds the value 48593.</p>