You need to navigate to Extensions > Modules. That's on the Joomla menu at the top of the page in Joomla backend. See the below screenshot.
Once there change Site to Administrator as shown below.
Now edit the "CB Admin Dropdown Menu" module as shown below.
Now click the "Menus" tab as shown below.
Next set "Plugin Menus" to "Show" as shown below.
You can also enable the new "Compact" mode there as well to put all the dropdown menus under a single top level Community Builder dropdown menu for a more compact display.