upgrade boot parent (#3352)

* make sure modules using java8

* move url matching code

* upgrade boot parent

* minor cleanup

spring-protobuf/pom.xml

@@ -7,10 +7,10 @@
     <name>spring-protobuf</name>
 
     <parent>
-        <artifactId>parent-boot-4</artifactId>
+        <artifactId>parent-boot-5</artifactId>
         <groupId>com.baeldung</groupId>
         <version>0.0.1-SNAPSHOT</version>
-        <relativePath>../parent-boot-4</relativePath>
+        <relativePath>../parent-boot-5</relativePath>
     </parent>
 
     <properties>