Set the source encoding for the build

mockito.spec

@@ -1,6 +1,6 @@
 Name:           mockito
 Version:        2.23.9
-Release:        2%{?dist}
+Release:        3%{?dist}
 Summary:        Tasty mocking framework for unit tests in Java
 License:        MIT
 URL:            https://site.mockito.org/
@@ -61,7 +61,7 @@ EOF
 %mvn_alias org.%{name}:%{name}-core org.%{name}:%{name}-all
 
 %build
-%mvn_build
+%mvn_build -- -Dproject.build.sourceEncoding=UTF-8
 
 %install
 %mvn_install
@@ -74,6 +74,9 @@ EOF
 %license LICENSE
 
 %changelog
+* Wed Dec 12 2018 Mat Booth <mat.booth@redhat.com> - 2.23.9-3
+- Set the source encoding for the build
+
 * Wed Dec 05 2018 Mat Booth <mat.booth@redhat.com> - 2.23.9-2
 - Re-add compatibility alias for 'mockito-all'