Use min_specialization on nightly

Amanieu · Amanieu · commit d6869a556962 · 2020-06-18T14:39:16.000+01:00
diff --git a/src/lib.rs b/src/lib.rs
@@ -19,7 +19,7 @@
         test,
         core_intrinsics,
         dropck_eyepatch,
-        specialization,
+        min_specialization,
         extend_one,
     )
 )]
