Move quote_string from trilogy and mysql2 adapters to abstract mysql adapter

Implementations of the method are exactly the same for trilogy and
mysql2 adapters so we will benefit from it being explicitly shared from
the abstract mysql adapter

Author: nvasilevski

activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb

@@ -659,6 +659,17 @@ def check_version # :nodoc:
         end
       end
 
+      #--
+      # QUOTING ==================================================
+      #++
+
+      # Quotes strings for use in SQL input.
+      def quote_string(string)
+        with_raw_connection(allow_retry: true, materialize_transactions: false) do |connection|
+          connection.escape(string)
+        end
+      end
+
       class << self
         def extended_type_map(default_timezone: nil, emulate_booleans:) # :nodoc:
           super(default_timezone: default_timezone).tap do |m|

activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb

@@ -115,17 +115,6 @@ def error_number(exception)
         exception.error_number if exception.respond_to?(:error_number)
       end
 
-      #--
-      # QUOTING ==================================================
-      #++
-
-      # Quotes strings for use in SQL input.
-      def quote_string(string)
-        with_raw_connection(allow_retry: true, materialize_transactions: false) do |connection|
-          connection.escape(string)
-        end
-      end
-
       #--
       # CONNECTION MANAGEMENT ====================================
       #++

activerecord/lib/active_record/connection_adapters/trilogy_adapter.rb

@@ -125,12 +125,6 @@ def supports_lazy_transactions?
         true
       end
 
-      def quote_string(string)
-        with_raw_connection(allow_retry: true, materialize_transactions: false) do |conn|
-          conn.escape(string)
-        end
-      end
-
       def connected?
         !(@raw_connection.nil? || @raw_connection.closed?)
       end