Remove sanitize_sql_like monkey-patch

I had added this many Rails versions ago during the recent upgrade process, because it was in latest Rails but not in the version of Rails I was using when replacing Elasticsearch with MySQL queries. We can remove it now!

app/models/color.rb

@@ -47,10 +47,4 @@ class Color < ApplicationRecord
     now = Time.now.in_time_zone('Pacific Time (US & Canada)')
     now.month == 4 && now.day == 1
   end
-
-  # TODO: Copied from modern Rails source, can delete once we're there!
-  def self.sanitize_sql_like(string, escape_character = "\\")
-    pattern = Regexp.union(escape_character, "%", "_")
-    string.gsub(pattern) { |x| [escape_character, x].join }
-  end
 end

app/models/item.rb

@@ -634,10 +634,4 @@ class Item < ApplicationRecord
   def self.build_proxies(ids)
     Item::ProxyArray.new(ids)
   end
-
-  # TODO: Copied from modern Rails source, can delete once we're there!
-  def self.sanitize_sql_like(string, escape_character = "\\")
-    pattern = Regexp.union(escape_character, "%", "_")
-    string.gsub(pattern) { |x| [escape_character, x].join }
-  end
 end

app/models/species.rb

@@ -29,10 +29,4 @@ class Species < ApplicationRecord
       I18n.translate('species.default_human_name')
     end
   end
-
-  # TODO: Copied from modern Rails source, can delete once we're there!
-  def self.sanitize_sql_like(string, escape_character = "\\")
-    pattern = Regexp.union(escape_character, "%", "_")
-    string.gsub(pattern) { |x| [escape_character, x].join }
-  end
 end