Accept equivalent mutations instead of disabling mutant

Per review: rather than suppressing the surviving mutations with
`# mutant:disable`, drop the redundant `Alchemrest::` prefixes. `Schema`
and `Transforms` resolve to the same constants inside `Alchemrest::Data`,
so the mutations are no longer generated and mutant reports 100% coverage
(14/14 killed). The `(&)` block-parameter fix is unchanged.

Author: frewsxcv

alchemrest/lib/alchemrest/data.rb

@@ -2,11 +2,8 @@
 
 module Alchemrest
   class Data
-    # Mutant only finds equivalent mutants here: these constants resolve the
-    # same with or without their Alchemrest:: prefix inside this namespace.
-    # mutant:disable
     def self.schema(&)
-      include Alchemrest::Data::Schema.new(**(yield Alchemrest::Transforms))
+      include Schema.new(**(yield Transforms))
     end
   end
 end