Remove icon setting from config, and let the theme control it

tests/reference/baseConfig_novelwriter.conf

@@ -1,8 +1,7 @@
 [Main]
-timestamp = 2021-12-31 16:45:32
+timestamp = 2022-10-26 11:19:49
 theme = default
 syntax = default_light
-icons = typicons_light
 guifont = 
 guifontsize = 11
 lastnotes = 0x0

tests/reference/guiPreferences_novelwriter.conf

@@ -1,9 +1,8 @@
 [Main]
-timestamp = 2021-12-31 16:45:34
+timestamp = 2022-10-26 11:19:51
 theme = default
 syntax = default_light
-icons = typicons_light
-guifont = Sans
+guifont = Cantarell
 guifontsize = 12
 lastnotes = 0x0
 guilang = en_GB
@@ -12,7 +11,7 @@ hidehscroll = True
 
 [Sizes]
 geometry = 1200, 650
-preferences = 670, 589
+preferences = 699, 614
 projcols = 200, 60, 140
 mainpane = 300, 800
 docpane = 400, 400