Fix U to `Un'.

Author: NoahStoryM

typed-racket-lib/typed-racket/base-env/base-env.rkt

@@ -985,7 +985,7 @@
                           [((-Immutable-HT a b) a (-> b b) (-> b)) (-Immutable-HT a b)]))]
 [hash-remove (-poly (a b) (-> (-Immutable-HT a b) Univ (-Immutable-HT a b)))]
 [hash-remove! (-poly (a b) (cl-> [((Un (-Mutable-HT a b) (-Weak-HT a b)) a) -Void]
-                                 [((U -Mutable-HashTableTop -Weak-HashTableTop) a) -Void]))]
+                                 [((Un -Mutable-HashTableTop -Weak-HashTableTop) a) -Void]))]
 [hash-clear! (-> -Mutable-HashTableTop -Void)]
 [hash-clear (-poly (a b) (-> (-Immutable-HT a b) (-Immutable-HT a b)))]
 [hash-copy-clear (-poly (a b) (cl-> [((-Immutable-HT a b)) (-Immutable-HT a b)]
@@ -1018,7 +1018,7 @@
                               [(-Mutable-HashTableTop) -Mutable-HashTableTop]
                               [((-Weak-HT a b)) (-Weak-HT a b)]
                               [(-Weak-HashTableTop) -Weak-HashTableTop]
-                              [((-HT a b)) (U (-Mutable-HT a b) (-Weak-HT a b))]))]
+                              [((-HT a b)) (Un (-Mutable-HT a b) (-Weak-HT a b))]))]
 [eq-hash-code (-> Univ -Fixnum)]
 [eqv-hash-code (-> Univ -Fixnum)]
 [equal-hash-code (-> Univ -Fixnum)]