Relax upper bound of package extra

NanoID.cabal

@@ -26,7 +26,7 @@ library
                      , base       >= 4.7   && < 5
                      , bytestring >= 0.10  && < 0.13
                      , cereal     >= 0.5.8 && < 0.5.9
-                     , extra      >= 1.6   && < 1.8
+                     , extra      >= 1.6   && < 1.9
                      , mwc-random >= 0.13  && < 0.16
                      , text       >= 1.2.3 && < 2.2