[Core] Indent stacktrace in pretty formatter

[mpkorstanje]

🤔 What's changed?

Renders the stack trace in the pretty formatter with the same indent as the step that failed it.

Before

[INFO] Running io.cucumber.skeleton.RunCucumberTest

Scenario: a few cukes               # io/cucumber/skeleton/belly.feature:3
  Given I have 42 cukes in my belly # io.cucumber.skeleton.StepDefinitions.I_have_cukes_in_my_belly(int)
    org.opentest4j.AssertionFailedError:
expected: "b"
 but was: "a"
  at java.base/jdk.internal.reflect.DirectConstructorHandleAccessor.newInstance(DirectConstructorHandleAccessor.java:62)
  at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:502)
  at io.cucumber.skeleton.StepDefinitions.I_have_cukes_in_my_belly(StepDefinitions.java:12)
  at ✽.I have 42 cukes in my belly(classpath:io/cucumber/skeleton/belly.feature:4)

After

[INFO] Running io.cucumber.skeleton.RunCucumberTest

Scenario: a few cukes               # io/cucumber/skeleton/belly.feature:3
  Given I have 42 cukes in my belly # io.cucumber.skeleton.StepDefinitions.I_have_cukes_in_my_belly(int)
      org.opentest4j.AssertionFailedError:
      expected: "b"
       but was: "a"
        at java.base/jdk.internal.reflect.DirectConstructorHandleAccessor.newInstance(DirectConstructorHandleAccessor.java:62)
        at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:502)
        at io.cucumber.skeleton.StepDefinitions.I_have_cukes_in_my_belly(StepDefinitions.java:12)
        at ✽.I have 42 cukes in my belly(classpath:io/cucumber/skeleton/belly.feature:4)

🏷️ What kind of change is this?

• 🐛 Bug fix (non-breaking change which fixes a defect)

📋 Checklist:

• I agree to respect and uphold the Cucumber Community Code of Conduct
• I've changed the behaviour of the code
  • I have added/updated tests to cover my changes.
• My change requires a change to the documentation.
  • I have updated the documentation accordingly.
• Users should know about my change
  • I have added an entry to the "Unreleased" section of the CHANGELOG, linking to this pull request.