Merge branch '3450055-remove-dedicated-environments' into '1.0.x'

nextjs.basefields.inc

nextjs.install

nextjs.links.action.yml

nextjs.links.contextual.yml

nextjs.links.task.yml

nextjs.module

nextjs.routing.yml

nextjs.services.yml

src/Element/NextjsEnvironmentSelect.php

src/Entity/NextjsEnvironment.php

src/Entity/NextjsEnvironmentInterface.php

src/Event/CacheWebhookEvent.php

src/EventSubscriber/CacheWebhookEventSubscriber.php

src/Form/NextjsEnvironmentForm.php

src/NextjsEnvironmentListBuilder.php

src/Repository/NextjsEnvironmentRepository.php

src/Repository/NextjsEnvironmentRepositoryInterface.php

src/Webhook/CacheWebhookDispatcher.php