fix: remove double % from layout width description

Update show.html.haml

app/views/profiles/preferences/show.html.haml

@@ -47,7 +47,7 @@
         = s_('Preferences|Layout width')
       = f.select :layout, layout_choices, {}, class: 'select2'
       .form-text.text-muted
-        = s_('Preferences|Choose between fixed (max. 1280px) and fluid (100%%) application layout.')
+        = s_('Preferences|Choose between fixed (max. 1280px) and fluid (%{percentage}) application layout.').html_safe % { percentage: '100%' }
     .form-group
       = f.label :dashboard, class: 'label-bold' do
         = s_('Preferences|Default dashboard')

locale/gitlab.pot

@@ -8299,7 +8299,7 @@ msgstr ""
 msgid "Preferences|Behavior"
 msgstr ""
 
-msgid "Preferences|Choose between fixed (max. 1280px) and fluid (100%%) application layout."
+msgid "Preferences|Choose between fixed (max. 1280px) and fluid (%{percentage}) application layout."
 msgstr ""
 
 msgid "Preferences|Choose what content you want to see on a project’s overview page."