Replace usage of deprecated Spring Framework methods

See gh-28642

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/web/server/ManagementServerProperties.java

@@ -102,7 +102,10 @@ public class ManagementServerProperties {
 	}
 
 	private String cleanBasePath(String basePath) {
-		String candidate = StringUtils.trimWhitespace(basePath);
+		String candidate = null;
+		if (StringUtils.hasLength(basePath)) {
+			candidate = basePath.strip();
+		}
 		if (StringUtils.hasText(candidate)) {
 			if (!candidate.startsWith("/")) {
 				candidate = "/" + candidate;

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/ServerProperties.java

@@ -262,7 +262,10 @@ public class ServerProperties {
 		}
 
 		private String cleanContextPath(String contextPath) {
-			String candidate = StringUtils.trimWhitespace(contextPath);
+			String candidate = null;
+			if (StringUtils.hasLength(contextPath)) {
+				candidate = contextPath.strip();
+			}
 			if (StringUtils.hasText(candidate) && candidate.endsWith("/")) {
 				return candidate.substring(0, candidate.length() - 1);
 			}

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/reactive/WebFluxProperties.java

@@ -52,7 +52,10 @@ public class WebFluxProperties {
 	}
 
 	private String cleanBasePath(String basePath) {
-		String candidate = StringUtils.trimWhitespace(basePath);
+		String candidate = null;
+		if (StringUtils.hasLength(basePath)) {
+			candidate = basePath.strip();
+		}
 		if (StringUtils.hasText(candidate)) {
 			if (!candidate.startsWith("/")) {
 				candidate = "/" + candidate;

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/logging/LoggingApplicationListener.java

@@ -306,7 +306,10 @@ public class LoggingApplicationListener implements GenericApplicationListener {
 	}
 
 	private void initializeSystem(ConfigurableEnvironment environment, LoggingSystem system, LogFile logFile) {
-		String logConfig = StringUtils.trimWhitespace(environment.getProperty(CONFIG_PROPERTY));
+		String logConfig = environment.getProperty(CONFIG_PROPERTY);
+		if (StringUtils.hasLength(logConfig)) {
+			logConfig = logConfig.strip();
+		}
 		try {
 			LoggingInitializationContext initializationContext = new LoggingInitializationContext(environment);
 			if (ignoreLogConfig(logConfig)) {