Add Maven property project.build.outputTimestamp for build

reproducibility

Author: garydgregory

src/changes/changes.xml

@@ -127,6 +127,7 @@ The <action> type attribute can be add,update,fix,remove.
       <action dev="ggregory" type="add"                due-to="Gary Gregory">Add IORunnable.noop().</action>
       <action dev="ggregory" type="add"                due-to="Gary Gregory">Add ChecksumInputStream and test #548.</action>
       <action dev="ggregory" type="add"                due-to="Gary Gregory">Add AbstractStreamBuilder.getReader().</action>
+      <action dev="ggregory" type="add"                due-to="Gary Gregory">Add Maven property project.build.outputTimestamp for build reproducibility.</action>
       <!--  UPDATE -->
       <action dev="ggregory" type="update"             due-to="Gary Gregory">Bump commons.bytebuddy.version from 1.14.10 to 1.14.11 #534.</action>
       <action dev="ggregory" type="update"             due-to="Gary Gregory">Bump org.apache.commons:commons-parent from 65 to 66.</action>