Update check file

It turns out with the fix to Constructors we don't generate the
a value for the intermediate field anymore. This seems great!
(scalac does generate the field, but it looks redundant)

Author: odersky

tests/run/variable-pattern-access.check

@@ -1,7 +1,6 @@
 # Fields of A:
 private final int A.a
 private final int A.b
-private final scala.Tuple2 A.$1$
 # Methods of A:
 public int A.a()
 public int A.b()