Do not crash if RDP is selected after regular GUI startup failed (#23…

…26410)

The ask_rd_question() function returns not only the credentials tuple,
but also the "use remote desktop" flag.

We correctly handled that in the regular case where we ask for user
password if user selected RDP instead of text mode.

But we missed that in the harder to test case where RDP is suggested
as an option to the user after regular locally running GUI startup
fails. Oops! :P

So handle the extra value and avoid the crash. :)

Resolves: rhbz#2326410

pyanaconda/display.py

@@ -406,7 +406,9 @@ def on_mutter_ready(observer):
                     "an RDP session to connect to this computer from another computer and "
                     "perform a graphical installation or continue with a text mode "
                     "installation?")
-        rdp_creds = ask_rd_question(anaconda, message)
+        # we aren't really interested in the use_rd flag so at least mark it like this
+        # to avoid linters being grumpy
+        _use_rd, credentials = ask_rd_question(anaconda, message)
 
     # if they want us to use RDP do that now
     if anaconda.gui_mode and flags.use_rd: