Allow using Action Mailbox on MySQL 5.5

Active Record still support MySQL 5.5 which doesn't support datetime
with precision.

https://github.com/rails/rails/blob/9e34df00039d63b5672315419e76f06f80ef3dc4/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb#L99-L101

So we should check `supports_datetime_with_precision?` on the
connection.

1 files changed, 5 insertions, 5 deletions

diff --git a/actiontext/test/dummy/db/schema.rb b/actiontext/test/dummy/db/schema.rb
index 39216ebd23..7f8f4dff4e 100644
--- a/actiontext/test/dummy/db/schema.rb
+++ b/actiontext/test/dummy/db/schema.rb
@@ -2,11 +2,11 @@
 # of editing this file, please use the migrations feature of Active Record to
 # incrementally modify your database, and then regenerate this schema definition.
 #
-# Note that this schema.rb definition is the authoritative source for your
-# database schema. If you need to create the application database on another
-# system, you should be using db:schema:load, not running all the migrations
-# from scratch. The latter is a flawed and unsustainable approach (the more migrations
-# you'll amass, the slower it'll run and the greater likelihood for issues).
+# This file is the source Rails uses to define your schema when running `rails
+# db:schema:load`. When creating a new database, `rails db:schema:load` tends to
+# be faster and is potentially less error prone than running all of your
+# migrations from scratch. Old migrations may fail to apply correctly if those
+# migrations use external dependencies or application code.
 #
 # It's strongly recommended that you check this file into your version control system.