Bump maven-compiler-plugin from 3.7.0 to 3.8.1 in /core

Bumps [maven-compiler-plugin](https://github.com/apache/maven-compiler-plugin) from 3.7.0 to 3.8.1.
- [Release notes](https://github.com/apache/maven-compiler-plugin/releases)
- [Commits](https://github.com/apache/maven-compiler-plugin/compare/maven-compiler-plugin-3.7.0...maven-compiler-plugin-3.8.1)

Signed-off-by: dependabot[bot] <support@github.com>

Closes #93

Change-Id: Ie2594c5bd1be8dc856a709451ad74600720ea79b
diff --git a/core/pom.xml b/core/pom.xml
index eba264c..c46867a 100644
--- a/core/pom.xml
+++ b/core/pom.xml
@@ -47,7 +47,7 @@
 			<plugin>
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-compiler-plugin</artifactId>
-				<version>3.7.0</version>
+				<version>3.8.1</version>
 				<configuration>
 					<compilerVersion>${java.version}</compilerVersion>
 					<source>${java.version}</source>