Use plain irb in debugging scenario

In Ruby 3.3, requiring readline does not load the real readline library
but falls back to reline by default. This creates odd output when the
terminal is not a real TTY and a prompt is used when getting input.
Because pry uses a prompt, this makes the interactive debugging scenario
fail.

This change works around this issue by switching to irb. Irb will not
use a prompt, possibly because the output is not a TTY.

See #910. Also, see
ruby/reline#616 for the resulting reline
issue.

features/03_testing_frameworks/cucumber/steps/command/debug_your_command_in_aruba.feature

@@ -10,15 +10,15 @@ Feature: Debug your command in cucumber-test-run
   Scenario: You can use a debug repl in your cli program
 
     If you want to debug an error, which only occurs in one of your
-    `cucumber`-tests, the `@debug`-tag becomes handy. This will use the
+    Cucumber tests, the `@debug`-tag becomes handy. This will use the
     DebugProcess runner, making your program use the default stdin, stdout and
     stderr streams so you can interact with it directly.
 
-    This will, for example, make `binding.pry` and `byebug` work in your
+    This will, for example, make `binding.irb` and `byebug` work in your
     program. However, Aruba steps that access the input and output of your
     program will not work.
 
-    We are going to demonstrate this using `pry`, but any other interactive
+    We are going to demonstrate this using `irb`, but any other interactive
     debugger for any other programming language should also work.
 
     Given an executable named "bin/aruba-test-cli" with:
@@ -27,8 +27,7 @@ Feature: Debug your command in cucumber-test-run
 
     foo = 'hello'
 
-    require 'pry'
-    binding.pry
+    binding.irb
     """
     And a file named "features/debug.feature" with:
     """cucumber
@@ -44,9 +43,9 @@ Feature: Debug your command in cucumber-test-run
     And I type "exit"
     Then the output should contain:
     """
-    [1] pry(main)> foo
-    => "hello"
-    [2] pry(main)> exit
+    foo
+    "hello"
+    exit
     """
 
   Scenario: Can handle announcers