Add spec for test suite

spec/test_suite_spec.cr

@@ -0,0 +1,18 @@
+require "./spec_helper"
+
+describe Spectator::TestSuite do
+  describe "#each" do
+    it "yields each example" do
+      group = Spectator::RootExampleGroup.new(Spectator::ExampleHooks.empty, Spectator::ExampleConditions.empty)
+      group.children = Array.new(5) do |index|
+        PassingExample.new(group, Spectator::Internals::SampleValues.empty).as(Spectator::ExampleComponent)
+      end
+      test_suite = Spectator::TestSuite.new(group)
+      examples = [] of Spectator::Example
+      test_suite.each do |example|
+        examples << example
+      end
+      examples.should eq(group.children)
+    end
+  end
+end