Update to ATL 4.12.0M3 (#843)

Author: dwagelaar

m2m-atl.aggrcon

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="ASCII"?>
 <aggregator:Contribution xmi:version="2.0" xmlns:xmi="http://www.omg.org/XMI" xmlns:aggregator="http://www.eclipse.org/cbi/p2repo/2011/aggregator/1.1.0" label="M2M ATL">
-  <repositories location="https://download.eclipse.org/mmt/atl/builds/milestone/S202505061820" description="M2M ATL">
+  <repositories location="https://download.eclipse.org/mmt/atl/builds/milestone/S202505101449" description="M2M ATL">
     <features name="org.eclipse.m2m.atl.feature.group" versionRange="4.12.0">
       <categories href="simrel.aggr#//@customCategories[identifier='Modeling']"/>
     </features>