Reproducible (#202)

Add the timestamp.

Fixes #197

Author: cstamas

pom.xml

@@ -117,6 +117,7 @@
     <maven.compiler.source>${maven.compiler.release}</maven.compiler.source>
     <maven.compiler.target>${maven.compiler.release}</maven.compiler.target>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <project.build.outputTimestamp>2023-01-01T00:00:00Z</project.build.outputTimestamp>
 
     <!-- Source headers -->
     <sisu.licenseHeader>https://raw.githubusercontent.com/eclipse-sisu/sisu-project/main/license-header-epl2.txt</sisu.licenseHeader>