Update Active Record Store docs to mention SQLite JSON usage

In addition to PosgreSQL JSON and MySQL JSON data types, developers need to use `store_accessor` instead of `store` when working with SQLite's JSON data type as well.

Author: fractaledmind

activerecord/lib/active_record/store.rb

@@ -25,8 +25,8 @@ module ActiveRecord
   # You can set custom coder to encode/decode your serialized attributes to/from different formats.
   # JSON, YAML, Marshal are supported out of the box. Generally it can be any wrapper that provides +load+ and +dump+.
   #
-  # NOTE: If you are using structured database data types (e.g. PostgreSQL +hstore+/+json+, or MySQL 5.7+
-  # +json+) there is no need for the serialization provided by {.store}[rdoc-ref:rdoc-ref:ClassMethods#store].
+  # NOTE: If you are using structured database data types (e.g. PostgreSQL +hstore+/+json+, MySQL 5.7+
+  # +json+, or SQLite 3.38+ +json+) there is no need for the serialization provided by {.store}[rdoc-ref:rdoc-ref:ClassMethods#store].
   # Simply use {.store_accessor}[rdoc-ref:ClassMethods#store_accessor] instead to generate
   # the accessor methods. Be aware that these columns use a string keyed hash and do not allow access
   # using a symbol.