Create service connections from Testcontainers-managed containers

Building upon the auto-configuration support for service connections,
this commit adds support for deriving connection details from a
Testcontainers-managed container. Several service-specific
annotations have been introduced. These annotations can be used on a
container field to indicate that it is a source of the details for
a service connection.

See gh-34658

Co-Authored-By: Phillip Webb <pwebb@vmware.com>
Co-Authored-By: Mortitz Halbritter <mkammerer@vmware.com>

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/howto/testing/testcontainers/serviceconnections/MyIntegrationTests.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2012-2023 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.boot.docs.howto.testing.testcontainers.serviceconnections;
+
+import org.junit.jupiter.api.Test;
+import org.testcontainers.containers.Neo4jContainer;
+import org.testcontainers.junit.jupiter.Container;
+import org.testcontainers.junit.jupiter.Testcontainers;
+
+import org.springframework.boot.test.autoconfigure.neo4j.Neo4jServiceConnection;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+@Testcontainers
+class MyIntegrationTests {
+
+	@Container
+	@Neo4jServiceConnection
+	static Neo4jContainer<?> neo4j = new Neo4jContainer<>("neo4j:4.2");
+
+	@Test
+	void myTest() {
+		// ...
+	}
+
+}

spring-boot-project/spring-boot-docs/src/main/kotlin/org/springframework/boot/docs/howto/testing/testcontainers/serviceconnections/MyIntegrationTests.kt

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2012-2023 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.boot.docs.howto.testing.testcontainers.serviceconnection
+
+import org.junit.jupiter.api.Test
+import org.springframework.boot.test.autoconfigure.neo4j.Neo4jServiceConnection;
+import org.springframework.boot.test.context.SpringBootTest
+import org.springframework.test.context.DynamicPropertyRegistry
+import org.springframework.test.context.DynamicPropertySource
+import org.testcontainers.containers.Neo4jContainer
+import org.testcontainers.junit.jupiter.Container
+import org.testcontainers.junit.jupiter.Testcontainers
+
+@SpringBootTest
+@Testcontainers
+internal class MyIntegrationTests {
+
+	@Test
+	fun myTest() {
+		// ...
+	}
+
+	companion object {
+
+		@Container
+		@Neo4jServiceConnection
+		var neo4j: Neo4jContainer<*> = Neo4jContainer<Nothing>("neo4j:4.2")
+
+	}
+
+}