MC-3864: Fix alpha value in background colour

- Resolve merge issue with tab items

Author: davemacaulay

app/code/Magento/PageBuilder/view/base/pagebuilder/content_type/tab_item.xml

@@ -60,11 +60,6 @@
                     </element>
                 </elements>
                 <converters>
-                    <converter name="preferred_color_format" component="Magento_PageBuilder/js/mass-converter/preferred-color-format">
-                        <config>
-                            <item name="background_color_format" value="background_color_format"/>
-                        </config>
-                    </converter>
                     <converter name="background_images" component="Magento_PageBuilder/js/mass-converter/background-images">
                         <config>
                             <item name="attribute_name" value="background_images"/>