docs: update demo to say that esc discard changes [skip ci] (#63)

demo/grid-pro-edit-column-demos.html

@@ -23,7 +23,7 @@ <h3>Edit Column</h3>
       When edit mode is activated for the cell, the following keys <b>change behavior</b>:
     </p>
     <ul>
-      <li><kbd>Esc</kbd> - save changes and exit the edit mode</li>
+      <li><kbd>Esc</kbd> - discard changes and exit the edit mode</li>
       <li><kbd>Enter</kbd> and <kbd>Shift</kbd> + <kbd>Enter</kbd> - save changes and exit the edit mode</li>
       <li><kbd>Tab</kbd> - exit the edit mode and focus the next editable cell</li>
       <li><kbd>Shift</kbd> + <kbd>Tab</kbd> - exit the edit mode and focus the previous editable cell</li>