RefDirectory: Add missing $NON-NLS suppression

Change-Id: I6afb4f86c3a8a06e5ea3128bf1b9b20c46ca158c
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/RefDirectory.java

@@ -1288,7 +1288,7 @@ public class RefDirectory extends RefDatabase {
 			try {
 				Files.delete(dir.toPath());
 			} catch (IOException e) {
-				LOG.warn("Unable to remove path {}", dir, e);
+				LOG.warn("Unable to remove path {}", dir, e); //$NON-NLS-1$
 				break;
 			}
 			dir = dir.getParentFile();