remove test that does not really test anything

spec/datadog/ci/contrib/knapsack_rspec/instrumentation_spec.rb

@@ -73,26 +73,4 @@ def devnull
     expect(test_spans).to all have_test_tag(:test_module_id)
     expect(test_spans).to all have_test_tag(:test_session_id)
   end
-
-  context "when collecting examples with knapsack_pro:rspec_test_example_detector" do
-    it "does not instrument this rspec session" do
-      with_new_rspec_environment do
-        ClimateControl.modify(
-          "KNAPSACK_PRO_CI_NODE_BUILD_ID" => "143",
-          "KNAPSACK_PRO_TEST_SUITE_TOKEN_RSPEC" => "example_token",
-          "KNAPSACK_PRO_FIXED_QUEUE_SPLIT" => "true"
-        ) do
-          expect(KnapsackPro::SlowTestFileDeterminer).to receive(:read_from_json_report).and_return([])
-
-          detector = KnapsackPro::TestCaseDetectors::RSpecTestExampleDetector.new
-          detector.generate_json_report
-        rescue ArgumentError
-          # suppress invalid API key error
-        end
-      end
-
-      expect(test_session_span).to be_nil
-      expect(test_spans).to be_empty
-    end
-  end
 end