Fix tests with Rails main

Rails main / 7.1.0.alpha introduced a change to improve typography by
default, by converting all apostrophes to be single quotation marks.
https://github.com/rails/rails/pull/45463

The change caused all our text based matching to fail, this updates the
tests to ensure compatibility.

Model tests were changed to test against the error type & information
rather than the translated string, which I think is an improvement
overall that should make them a little less brittle. I thought of using
[of_kind?] but that isn't available on all Rails versions we currently
support, while `added?` is. The drawback is that `added?` require full
details like the `:confirmation` example which requires the related
attribute that is being confirmed, but that's a small price to pay.

Integration tests were changed to match on a regexp that accepts both
quotes. I could've used a simple `.` to match anything there, but
thought I'd just keep it specific for clarity on what it is really
expected to match there. Plus, since it's integration testing against a
rendered response body, it's better to match the actual text rather than
resort on other ways. (like using I18n directly, etc.)

[of_kind?] https://api.rubyonrails.org/classes/ActiveModel/Errors.html#method-i-of_kind-3F

test/integration/confirmable_test.rb

@@ -178,13 +178,13 @@ class ConfirmationTest < Devise::IntegrationTest
   test "should not be able to confirm an email with a blank confirmation token" do
     visit_user_confirmation_with_token("")
 
-    assert_contain "Confirmation token can't be blank"
+    assert_contain %r{Confirmation token can['’]t be blank}
   end
 
   test "should not be able to confirm an email with a nil confirmation token" do
     visit_user_confirmation_with_token(nil)
 
-    assert_contain "Confirmation token can't be blank"
+    assert_contain %r{Confirmation token can['’]t be blank}
   end
 
   test "should not be able to confirm user with blank confirmation token" do
@@ -193,7 +193,7 @@ class ConfirmationTest < Devise::IntegrationTest
 
     visit_user_confirmation_with_token("")
 
-    assert_contain "Confirmation token can't be blank"
+    assert_contain %r{Confirmation token can['’]t be blank}
   end
 
   test "should not be able to confirm user with nil confirmation token" do
@@ -202,7 +202,7 @@ class ConfirmationTest < Devise::IntegrationTest
 
     visit_user_confirmation_with_token(nil)
 
-    assert_contain "Confirmation token can't be blank"
+    assert_contain %r{Confirmation token can['’]t be blank}
   end
 
   test 'error message is configurable by resource name' do

test/integration/recoverable_test.rb

@@ -173,7 +173,7 @@ class PasswordTest < Devise::IntegrationTest
     assert_response :success
     assert_current_url '/users/password'
     assert_have_selector '#error_explanation'
-    assert_contain "Password confirmation doesn't match Password"
+    assert_contain %r{Password confirmation doesn['’]t match Password}
     assert_not user.reload.valid_password?('987654321')
   end
 

test/integration/registerable_test.rb

@@ -112,7 +112,7 @@ class RegistrationTest < Devise::IntegrationTest
     assert_template 'registrations/new'
     assert_have_selector '#error_explanation'
     assert_contain "Email is invalid"
-    assert_contain "Password confirmation doesn't match Password"
+    assert_contain %r{Password confirmation doesn['’]t match Password}
     assert_contain "2 errors prohibited"
     assert_nil User.to_adapter.find_first
 
@@ -251,7 +251,7 @@ class RegistrationTest < Devise::IntegrationTest
     fill_in 'current password', with: '12345678'
     click_button 'Update'
 
-    assert_contain "Password confirmation doesn't match Password"
+    assert_contain %r{Password confirmation doesn['’]t match Password}
     assert_not User.to_adapter.find_first.valid_password?('pas123')
   end