Satisfy -Wincomplete-uni-patterns with _ex2

Author: philderbeast

hackage-security/src/Hackage/Security/TUF/Patterns.hs

@@ -323,9 +323,8 @@ _ex1 = matchDelegation del "A/x/y/z.foo"
             )
 
 _ex2 :: Maybe String
-_ex2 = matchDelegation del "A/x/y/z.foo"
-  where
-    Right del = parseDelegation "A/*/*/*.foo" "B/*/C/*/*.bar"
+_ex2 = either (const Nothing) (`matchDelegation` "A/x/y/z.foo")
+  (parseDelegation "A/*/*/*.foo" "B/*/C/*/*.bar")
 
 _ex3 :: Either String Delegation
 _ex3 = parseDelegation "foo" "*/bar"