Avoid problems with Surefire when building samples with JDK 10

See gh-12028

spring-boot-samples/pom.xml

@@ -247,4 +247,24 @@
 			</plugin>
 		</plugins>
 	</build>
+	<profiles>
+		<profile>
+			<id>java10</id>
+			<activation>
+				<jdk>10</jdk>
+			</activation>
+			<properties>
+				<maven-surefire-plugin.version>2.21.0-SNAPSHOT</maven-surefire-plugin.version>
+			</properties>
+			<pluginRepositories>
+				<pluginRepository>
+					<id>apache-snapshots</id>
+					<url>https://repository.apache.org/content/groups/snapshots</url>
+					<snapshots>
+						<enabled>true</enabled>
+					</snapshots>
+				</pluginRepository>
+			</pluginRepositories>
+		</profile>
+	</profiles>
 </project>