Disable trunk listener when running under knapsack_pro:rspec_test_example_detector (#937)

`knapsack_pro:rspec_test_example_detector` instantiates all tests in a file to determine how to split by test examples ([reference](https://docs.knapsackpro.com/ruby/split-by-test-examples/)). This step is done before actually running the tests. When that happens, the RSpec reporter reports all test examples as passing, despite the fact that they're not actually run.

This change checks if the command line contains "knapsack_pro:rspec_test_example_detector", and if so, disables test collection and uploading.

Author: mmatheson

rspec-trunk-flaky-tests/lib/trunk_spec_helper.rb

@@ -55,8 +55,21 @@ def escape(str)
   str.dump[1..-2]
 end
 
+# Knapsack example detector instantiates all test cases in order to determine how to shard them
+# These instantiations should not generate test bundles, so we
+# disable the gem when running under knapsack_pro:rspec_test_example_detector
+def knapsack_detector_mode?
+  knapsack_detector_command?
+end
+
+def knapsack_detector_command?
+  command_line = "#{$PROGRAM_NAME} #{ARGV.join(' ')}".strip
+  command_line.include?('knapsack_pro:rspec_test_example_detector')
+end
+
 def trunk_disabled
-  ENV['DISABLE_RSPEC_TRUNK_FLAKY_TESTS'] == 'true' || ENV['TRUNK_ORG_URL_SLUG'].nil? || ENV['TRUNK_API_TOKEN'].nil?
+  knapsack_detector_mode? || ENV['DISABLE_RSPEC_TRUNK_FLAKY_TESTS'] == 'true' ||
+    ENV['TRUNK_ORG_URL_SLUG'].nil? || ENV['TRUNK_API_TOKEN'].nil?
 end
 
 # we want to cache the test report so we can add to it as we go and reduce the number of API calls