Tidy up imports.

Author: aardvark179

src/main/java/org/truffleruby/core/FinalizationService.java

@@ -17,8 +17,6 @@
 
 import org.truffleruby.RubyContext;
 import org.truffleruby.core.thread.ThreadManager;
-import org.truffleruby.language.control.RaiseException;
-import org.truffleruby.language.control.TerminationException;
 
 import com.oracle.truffle.api.object.DynamicObject;