Adapt exit spec's expected output for TruffleRuby

Author: eregon

spec/integration/spec_file_load_errors_spec.rb

@@ -95,6 +95,17 @@
         While loading ./helper_with_exit.rb an `exit` / `raise SystemExit` occurred, RSpec will now quit.
         Failure/Error: Unable to find org/jruby/RubyKernel.java to read failed line
 
+        SystemExit:
+          exit
+        # ./helper_with_exit.rb:1#{spec_line_suffix}
+      EOS
+    elsif RSpec::Support::Ruby.truffleruby?
+      # No extra ./helper_with_exit.rb:1:in `exit' line on truffleruby, Kernel#exit is defined in Ruby code
+      expect(output).to eq unindent(<<-EOS)
+
+        While loading ./helper_with_exit.rb an `exit` / `raise SystemExit` occurred, RSpec will now quit.
+        Failure/Error: exit 999
+
         SystemExit:
           exit
         # ./helper_with_exit.rb:1#{spec_line_suffix}