Added null check on spring boot profiles

Author: sapessi

aws-serverless-java-container-spring/src/main/java/com/amazonaws/serverless/proxy/spring/SpringBootLambdaContainerHandler.java

@@ -113,7 +113,9 @@ protected void handleRequest(AwsProxyHttpServletRequest containerRequest, AwsHtt
 
         // wire up the application context on the first invocation
         if (!initialized) {
-            System.setProperty("spring.profiles.active", String.join(",", springProfiles));
+            if (springProfiles != null && springProfiles.length > 0) {
+                System.setProperty("spring.profiles.active", String.join(",", springProfiles));
+            }
             SpringServletContainerInitializer springServletContainerInitializer = new SpringServletContainerInitializer();
             LinkedHashSet<Class<?>> webAppInitializers = new LinkedHashSet<>();
             webAppInitializers.add(springBootInitializer);