Make sidekiq and resque integration tests work in CI

Since f55ecc6a, the integration test of sidekiq and resque is not working
in CI.
https://travis-ci.org/rails/rails/jobs/251783876

Because f55ecc6a required a password to access redis.
Therefore, handling by passing passwords when connecting to redis.

Use frozen-string-literal in ActiveJob

[ci skip] Updated language on validations.

Update MessageEncryptor example to use dynamic key length

Treat secrets as binary

Load environment file in `dbconsole` command

Prepare AP and AR to be frozen string friendly

Use frozen-string-literal in ActiveSupport

Currently the environment file is not loaded in `dbconsole` command.
Therefore, for example, if use encrypted secrets values in database.yml,
`read_encrypted_secrets` will not be true, so the value can not be
used correctly.

Fixes #29717

Until Rails 5.1.1 secrets was treated as binary inside Rails.
https://github.com/rails/rails/blob/v5.1.1/railties/lib/rails/secrets.rb#L59
https://github.com/rails/rails/blob/v5.1.1/railties/lib/rails/secrets.rb#L63

However, it is treated as String in Rails 5.1.2(changed by 157db872).
https://github.com/rails/rails/blob/v5.1.2/railties/lib/rails/secrets.rb#L104
https://github.com/rails/rails/blob/v5.1.2/railties/lib/rails/secrets.rb#L108

As a result, when upgrading from Rails 5.1.1 to 5.1.2, to write the value
treated as binary using `File.write`, causing an error.

In order to avoid `UndefinedConversionError`, fixed it to treat it as
binary like 5.1.1.
Fixes #29696

Don't allow uuids with orphan curly braces

Skip query cache for in_batches and friends

Don't translate non-database exceptions.

Fix bug with long stream identifiers when using Postgres adapter

Improve the performance of writing attributes

Add `rails secrets:show` command

Do not update `secrets.yml.enc` when secretes do not change

Use `information_schema` to extract `generation_expression` for MariaDB

Fix default `CURRENT_TIMESTAMP` in schema dumping for MariaDB 10.2

Clarify i18n guide for how pluralization rules work by default

It's possible for developers toadd a custom driver and then call it
using `driven_by`. Because we were only skipping `register` for
`:rack_test` that meant any custom driver would attempt to be registered
as well.

The three listed here are special because Rails registers them with
special options. If you're registering your own custom driver then you
don't want to separately register that driver.

Fixes #29688

Update default app files in app_generator_test

The guide misleadingly indicates that the I18n gem will apply the CLDR pluralization rules for each language. This is not the case; only the English algorithm, with support for :zero, :one, and :other, is available by default. Locale-specific pluralization rules require additional configuration and must be supplied by the application (or by another gem).

The uuid validation regex was allowing uuids to have a single leading
curly brace or single trailing curly brace. Saving with such a uuid
would cause Postgres to generate an exception even though the record
seemed valid. With this change, the regex requires both a leading *and*
a trailing curly brace or neither to be valid.

Add ActiveModel::Errors#merge!

ActiveModel::Errors#merge! allows ActiveModel::Errors to append errors from
a separate ActiveModel::Errors instance onto their own.

Example:

    person = Person.new
    person.errors.add(:name, :blank)

    errors = ActiveModel::Errors.new(Person.new)
    errors.add(:name, :invalid)

    person.errors.merge!(errors)
    puts person.errors.messages
    # => { name: ["can't be blank", "is invalid"] }

Currently, if open a file with `secrets:edit` command, `secrets.yml.enc`
will be changed even if its contents do not change.

Therefore, even if only want to check secrets, the difference will come
out. This is a little inconvenient.

As a fix to the above problem, when content does not change,
`secrets.yml.ecn` is fixed so that it is not changed.

Since MariaDB 10.2, `CURRENT_TIMESTAMP` is shown as a function
(`current_timestamp()`). Fix matching column default to address that
case.

Fixes #29698.

Since MariaDB 10.2.5, `information_schema` supports Virtual Columns.

Fixes #29670.