Add inadvertently-omitted 'included' test.

79 tests, 108 assertions, 0 failures, 0 errors, 0 skips
Coverage: 909 / 909 LOC (100.0%) covered.
RuboCop: 11 files inspected, no offenses detected
Flay: Total score 0
Flog: Total 329.8; method average 4.6; max 9.8 (CryptIdent::SignUp#create_result)
Reek: 0 total warnings
Inch: Nothing to suggest

test/crypt_ident/included_test.rb

@@ -1,17 +0,0 @@
-# frozen_string_literal: true
-
-require 'test_helper'
-
-include CryptIdent
-
-describe 'CryptIdent.included' do
-  it 'defines the module-added instance variable' do
-    actual = CryptIdent.instance_variable_get(:@cryptid_config)
-    expect(actual).must_equal CryptIdent.configure_crypt_ident
-  end
-
-  it 'adds the cryptid_config reader method to the module' do
-    expected = CryptIdent.configure_crypt_ident
-    expect(CryptIdent.cryptid_config).must_equal expected
-  end
-end