Fix build warnings

* Set <relativePath/> on <parent> element to prevent warnings about pointing to the wrong parent.
* Fix package name - avoid warning about invalid javadoc.

Partially resolves #156

function-samples/uppercase-processor/pom.xml

@@ -6,6 +6,7 @@
     <groupId>org.springframework.boot</groupId>
     <artifactId>spring-boot-starter-parent</artifactId>
     <version>2.3.1.RELEASE</version>
+    <relativePath/>
   </parent>
 
   <groupId>org.springframework.cloud.dataflow.samples</groupId>