eclipse-core: add Provide-Capability header to manifest

This clears launch errors in recent Eclipse verisons.
diff --git a/eclipse/eclipse-core/META-INF/MANIFEST.MF b/eclipse/eclipse-core/META-INF/MANIFEST.MF
index ef3cc04..706d51c 100644
--- a/eclipse/eclipse-core/META-INF/MANIFEST.MF
+++ b/eclipse/eclipse-core/META-INF/MANIFEST.MF
@@ -57,3 +57,4 @@
  org.apache.sling.ide.eclipse.core.progress,
  org.apache.sling.ide.eclipse.internal.validation;x-friends:="org.apache.sling.ide.eclipse-test"
 Service-Component: OSGI-INF/TraceCommandExecutionEventsHandler.xml, OSGI-INF/Tracer.xml
+Provide-Capability: osgi.service;objectClass=org.apache.sling.ide.log.Logger