feat(version): Use simpler version.rb file

lib/version.rb

@@ -1,11 +1,6 @@
 # Expose gem version
 class AlgoliaSearchJekyllVersion
-  MAJOR = 0
-  MINOR = 5
-  PATCH = 1
-  BUILD = nil
-
   def self.to_s
-    [MAJOR, MINOR, PATCH, BUILD].compact.join('.')
+    '0.5.1'
   end
 end