Fixes for enumerating examples

src/spectator/given_example_group.cr

@@ -9,18 +9,20 @@ module Spectator
     end
 
     def example_count
-      super.example_count * @collection.size
+      super * @collection.size
     end
 
     def all_examples
       Array(Example).new(example_count).tap do |array|
         examples = super
+        @collection.each do |value|
           examples.each do |example|
             @mapping[example] = value
           end
           array.concat(examples)
         end
       end
+    end
 
     def value_for(example : Example) : T
       @mapping[example]