Allow creation of SpringProfileArbiter without Environment

See gh-39403

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/log4j2/SpringProfileArbiter.java

@@ -95,8 +95,7 @@ Builder setName(String name) {
 		public SpringProfileArbiter build() {
 			Environment environment = Log4J2LoggingSystem.getEnvironment(this.loggerContext);
 			if (environment == null) {
-				statusLogger.warn("Cannot create Arbiter, no Spring Environment available");
-				return null;
+				statusLogger.debug("Creating Arbiter without a Spring Environment");
 			}
 			String name = this.configuration.getStrSubstitutor().replace(this.name);
 			String[] profiles = StringUtils.trimArrayElements(StringUtils.commaDelimitedListToStringArray(name));