Update mediawiki_selenium Ruby gem to the latest version

Bug: 117976
Change-Id: I567880afcf7dc5d70e6d4edef1db16d7923ae31c

tests/browser/features/support/pages/main_page.rb

@@ -1,8 +1,7 @@
 class MainPage
 	include PageObject
 
-	include URL
-	page_url URL.url("Main_Page")
+	page_url "Main_Page"
 
 	span(:cog, title: "Language settings")
 	a(:create_a_book, text: "Create a book")
@@ -18,7 +17,7 @@ class MainPage
 	button(:search_button, id: "searchButton")
 
   def non_interlanguage_links_use_autonym_font?
-		@browser.elements(css: "#p-lang li:not(.interlanguage-link)").collect do |element|
+		browser.elements(css: "#p-lang li:not(.interlanguage-link)").collect do |element|
 			element.style("font-family")
 		end.to_s.match(/Autonym/) != nil
 	end