[mirotalksfu] - improve collaborative whiteboard

public/views/Room.html

@@ -1211,8 +1211,8 @@ access to use this app.
                         </button>
                         <div class="dropdown-menu text-start" aria-labelledby="whiteboardDropDownMenu">
                             <button id="whiteboardImgFileBtn"><i class="far fa-image"></i> Add image file</button>
-                            <button id="whiteboardPdfFileBtn"><i class="far fa-file-pdf"></i> Add pdf file</button>
                             <button id="whiteboardImgUrlBtn"><i class="fas fa-link"></i> Add image URL</button>
+                            <button id="whiteboardPdfFileBtn"><i class="far fa-file-pdf"></i> Add pdf file</button>
                             <button id="whiteboardTextBtn"><i class="fas fa-spell-check"></i> Add text</button>
                             <button id="whiteboardLineBtn"><i class="fas fa-slash"></i> Add line</button>
                             <button id="whiteboardRectBtn"><i class="far fa-square"></i> Add rectangle</button>