Remove support for setting default CacheAwareContextLoaderDelegate

The ability to set a system property to change the default
CacheAwareContextLoaderDelegate was only needed by the Spring Native
project in the Spring Framework 5.3.x line and should not be used by
other projects.

This commit therefore reverts the changes made in conjunction with
gh-27540.

Closes gh-29061

spring-test/src/test/java/org/springframework/test/context/support/CustomDefaultCacheAwareContextLoaderDelegateTests.java

@@ -1,95 +0,0 @@
-/*
- * Copyright 2002-2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.springframework.test.context.support;
-
-import org.junit.jupiter.api.Test;
-import org.junit.platform.testkit.engine.EngineTestKit;
-
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.context.ApplicationContext;
-import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.Configuration;
-import org.springframework.context.support.GenericApplicationContext;
-import org.springframework.core.SpringProperties;
-import org.springframework.test.context.CacheAwareContextLoaderDelegate;
-import org.springframework.test.context.MergedContextConfiguration;
-import org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate;
-import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
-
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.platform.engine.discovery.DiscoverySelectors.selectClass;
-
-/**
- * Integration tests for configuring a custom default {@link CacheAwareContextLoaderDelegate}
- * via {@link SpringProperties}.
- *
- * @author sbrannen
- * @since 5.3.11
- */
-class CustomDefaultCacheAwareContextLoaderDelegateTests {
-
-	@Test
-	void customDefaultCacheAwareContextLoaderDelegateConfiguredViaSpringProperties() {
-		String key = CacheAwareContextLoaderDelegate.DEFAULT_CACHE_AWARE_CONTEXT_LOADER_DELEGATE_PROPERTY_NAME;
-
-		try {
-			SpringProperties.setProperty(key, AotCacheAwareContextLoaderDelegate.class.getName());
-
-			EngineTestKit.engine("junit-jupiter")//
-					.selectors(selectClass(TestCase.class))//
-					.execute()//
-					.testEvents()//
-					.assertStatistics(stats -> stats.started(1).succeeded(1).failed(0));
-		}
-		finally {
-			SpringProperties.setProperty(key, null);
-		}
-	}
-
-
-	@SpringJUnitConfig
-	static class TestCase {
-
-		@Test
-		void test(@Autowired String foo) {
-			// foo will be "bar" unless the AotCacheAwareContextLoaderDelegate is registered.
-			assertThat(foo).isEqualTo("AOT");
-		}
-
-
-		@Configuration
-		static class Config {
-
-			@Bean
-			String foo() {
-				return "bar";
-			}
-		}
-	}
-
-	static class AotCacheAwareContextLoaderDelegate extends DefaultCacheAwareContextLoaderDelegate {
-
-		@Override
-		protected ApplicationContext loadContextInternal(MergedContextConfiguration mergedContextConfiguration) {
-			GenericApplicationContext applicationContext = new GenericApplicationContext();
-			applicationContext.registerBean("foo", String.class, () -> "AOT");
-			applicationContext.refresh();
-			return applicationContext;
-		}
-	}
-
-}