Update gradle main class config

The main class is incorrect ("example.Config" does not exist), so the lambda function cannot recognize the main class of the jar file.

spring-cloud-function-samples/function-sample-aws/build.gradle

@@ -50,7 +50,7 @@ assemble.dependsOn = [shadowJar, thinJar]
 
 jar {
 	manifest {
-		attributes 'Main-Class': 'example.Config'
+		attributes 'Main-Class': 'example.FunctionConfiguration'
 	}
 }
 
@@ -90,4 +90,4 @@ dependencies {
 	compileOnly("com.amazonaws:aws-lambda-java-events:${awsLambdaEventsVersion}")
 	compileOnly("com.amazonaws:aws-lambda-java-core:${awsLambdaCoreVersion}")
 	testCompile('org.springframework.boot:spring-boot-starter-test')
-}
+}