SubmoduleValidator: Remove unused import of ConfigConstants

Change-Id: I6afe5690bf9d1f1f4d414aa618daefc8b48d217e
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

org.eclipse.jgit/src/org/eclipse/jgit/internal/submodule/SubmoduleValidator.java

@@ -52,7 +52,6 @@ import java.text.MessageFormat;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.internal.JGitText;
 import org.eclipse.jgit.lib.Config;
-import org.eclipse.jgit.lib.ConfigConstants;
 
 /**
  * Validations for the git submodule fields (name, path, uri).