Update dependency org.apache.maven.plugins:maven-compiler-plugin to v3.8.1

Closes: #1995

Author: mpkorstanje

archetype/src/main/resources/archetype-resources/pom.xml

@@ -43,7 +43,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
-                <version>3.7.0</version>
+                <version>3.8.1</version>
                 <configuration>
                     <encoding>UTF-8</encoding>
                     <source>1.8</source>

archetype/src/test/resources/projects/should-generate-project/reference/pom.xml

@@ -43,7 +43,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
-                <version>3.7.0</version>
+                <version>3.8.1</version>
                 <configuration>
                     <encoding>UTF-8</encoding>
                     <source>1.8</source>