Functional tests fail on Drupal 11.4: Standard profile no longer provides Page/Article content types

Problem/Motivation

Drupal 11.4 removed the Article and Basic page content types from the Standard installation profile. Many of the module's functional tests rely on those content types existing (through DomainTestBase and the Standard profile), so they now fail on Drupal 11.4 with Behat/Mink ExpectationException errors on node forms and content assertions.

Around 25 functional test classes are affected across every submodule, for example DomainSourcePathAliasTest, DomainAccessPermissionsTest, DomainEntityAccessTest, DomainAccessDefaultValueTest, DomainContentCountTest and DomainSourceEntityReferenceTest.

This is unrelated to the PHPStan work in #3612201: that pipeline is green on phpstan, phpcs and cspell but red on phpunit for this reason.

Steps to reproduce

Run the functional test suite against Drupal 11.4.

Proposed resolution

Stop relying on the Standard profile providing the page and article content types. Create the required content types explicitly in the test setup (for example in DomainTestBase::setUp()) and adjust the field and form-display configuration the tests depend on.

Remaining tasks

Write a merge request; review; commit.