test: add assertion for executing App.main with empty args

[AlMartinezUy]

Pull Request Template

What does this PR do?

This PR adds an additional assertion to the AppTest test class in the
abstract-document module. The new assertion verifies that calling
App.main with an empty String[] argument does not throw any exception.

This complements the existing assertion that checks the behavior when the
main method is invoked with a null argument.

No production code is modified. This PR solely improves test coverage and
validates expected behavior under different argument conditions.

[github-actions]

PR Summary

This PR strengthens test coverage by adding an assertion that App.main is safe to call with an empty String[] argument, complementing the existing check for null arguments. No production code changes are introduced. README formatting was also improved to separate the Introduction and Getting Started sections for clarity.

Changes

File	Summary
README.md	Adjusted the README to restructure sections: split Introduction and Getting Started, refined messaging about design patterns, and updated content for clarity and flow; minor formatting fixes included.
abstract-document/src/test/java/com/iluwatar/abstractdocument/AppTest.java	Extended shouldExecuteAppWithoutException to also verify that App.main(new String[]{}) does not throw, in addition to the existing null-check.

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autogenerated by presubmit.ai

[AlMartinezUy]

Hi! I noticed that the checks failed, but the failure appears unrelated to the
changes in this PR. The modification only affects a small test case in the
abstract-document module.

Please let me know if you'd like me to adjust anything.

[github-actions]

This PR is stale because it has been open 60 days with no activity.

[github-actions]

✅ LGTM!

Review Summary

Commits Considered (3)

• 94b3a6f: Merge branch 'master' into improve-app-test
• 2169fe9: test: add assertion for executing App.main with empty args
• 664b5f7: Fix duplicated README formatting: separate Introduction and Getting Started sections

Files Processed (2)

• README.md (1 hunk)
• abstract-document/src/test/java/com/iluwatar/abstractdocument/AppTest.java (1 hunk)

Actionable Comments (0)

Skipped Comments (2)

• abstract-document/src/test/java/com/iluwatar/abstractdocument/AppTest.java [43-43]

  readability: "Isolate null-args path into its own test"

• abstract-document/src/test/java/com/iluwatar/abstractdocument/AppTest.java [46-49]

  enhancement: "Test empty-args path for App.main"

[AlMartinezUy]

Hi! I've updated the branch with the latest master changes. One of the checks is now passing successfully. The Java PR Builder failure seems unrelated to my changes, as this PR only adds a small test case for empty arguments in the abstract-document module. Could a maintainer please take a look when possible? Thanks!