[Documentation:Developer] Typos on Docker UI (#611)

Fix typos on Docker UI page

_docs/instructor/autograding/docker_ui.md

@@ -7,7 +7,7 @@ Depending on your assignment, you may need to install new docker
 images on the system to perform autograding. You can do this via the
 Docker UI page available to instructors with the role `Faculty`.  To
 check if you have access, click on "My Profile" from the left sidebar.
-If you don't see "Access Level: Faculty", as your sysadmin to give you
+If you don't see "Access Level: Faculty", ask your sysadmin to give you
 this access.
 
 From the Docker UI page, you can see what capabilities are
@@ -19,7 +19,7 @@ disabled or there was an error associated with the updating of
 said machine. In the case of an error, there will be an area with
 the error within the System Wide Information section.
 
-### Adding Image
+### Adding Images
 
 To add an image to a capability, you must first select the
 capability to add to. Next you must provide a valid Docker