Upgrade Maven plugins in build

Author: mhalbritter

pom.xml

@@ -101,7 +101,7 @@
 				<plugin>
 					<groupId>org.codehaus.mojo</groupId>
 					<artifactId>flatten-maven-plugin</artifactId>
-					<version>1.7.0</version>
+					<version>1.7.1</version>
 				</plugin>
 				<plugin>
 					<groupId>io.spring.javaformat</groupId>
@@ -141,7 +141,7 @@
 						<dependency>
 							<groupId>com.puppycrawl.tools</groupId>
 							<artifactId>checkstyle</artifactId>
-							<version>10.21.4</version>
+							<version>10.26.1</version>
 						</dependency>
 						<dependency>
 							<groupId>io.spring.javaformat</groupId>
@@ -155,16 +155,6 @@
 					<artifactId>frontend-maven-plugin</artifactId>
 					<version>1.15.1</version>
 				</plugin>
-				<plugin>
-					<groupId>org.apache.maven.plugins</groupId>
-					<artifactId>maven-resources-plugin</artifactId>
-					<version>3.3.1</version>
-				</plugin>
-				<plugin>
-					<groupId>org.apache.maven.plugins</groupId>
-					<artifactId>maven-surefire-plugin</artifactId>
-					<version>3.5.3</version>
-				</plugin>
 				<plugin>
 					<groupId>org.apache.maven.plugins</groupId>
 					<artifactId>maven-compiler-plugin</artifactId>

start-site/src/main/java/io/spring/start/site/extension/dependency/testcontainers/TestContainersApplicationCodeProjectContributor.java

@@ -45,12 +45,12 @@
 abstract class TestContainersApplicationCodeProjectContributor<T extends TypeDeclaration, C extends CompilationUnit<T>, S extends SourceCode<T, C>>
 		implements ProjectContributor {
 
-	public static final ClassName TEST_CONFIGURATION_CLASS_NAME = ClassName
+	private static final ClassName TEST_CONFIGURATION_CLASS_NAME = ClassName
 		.of("org.springframework.boot.test.context.TestConfiguration");
 
-	public static final ClassName BEAN_CLASS_NAME = ClassName.of("org.springframework.context.annotation.Bean");
+	private static final ClassName BEAN_CLASS_NAME = ClassName.of("org.springframework.context.annotation.Bean");
 
-	public static final ClassName SERVICE_CONNECTION_CLASS_NAME = ClassName
+	private static final ClassName SERVICE_CONNECTION_CLASS_NAME = ClassName
 		.of("org.springframework.boot.testcontainers.service.connection.ServiceConnection");
 
 	private static final ClassName DOCKER_IMAGE_NAME_CLASS_NAME = ClassName