Migrate from Travis CI to GitHub Actions with danger-pr-comment workflow.

[dblock]

Migrates the project from Travis CI to GitHub Actions.

• Adds .github/workflows/test.yml with Ruby test workflow
• Adds .github/workflows/rubocop.yml with RuboCop linting workflow
• Adds .github/workflows/danger.yml with danger-pr-comment workflow for PR comments
• Removes .travis.yml
• Updates README.md to reflect GitHub Actions CI status badge
• Updates CHANGELOG.md with PR reference

Both test and RuboCop workflows run on all branches and pull requests using Ruby 3.4.

[dblock]

@copilot check this out?

[Copilot]

@dblock I've opened a new pull request, #46, to work on those changes. Once the pull request is ready, I'll request review from you.

[Copilot]

Pull request overview

This PR migrates the project's continuous integration from Travis CI to GitHub Actions, implementing a more modern CI/CD approach with separate workflows for testing, linting, and pull request automation.

Key Changes:

• Replaced Travis CI with three GitHub Actions workflows: test (runs RSpec tests), RuboCop (linting), and Danger (PR automation with danger-pr-comment)
• Updated dependencies by adding danger-pr-comment gem and removing version constraints from danger-changelog and danger-toc
• Updated Dangerfile to use danger-pr-comment plugin and stricter check methods (check!)

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
.github/workflows/test.yml	Adds test workflow to run RSpec tests on Ruby 3.4
.github/workflows/rubocop.yml	Adds RuboCop linting workflow on Ruby 3.4
.github/workflows/danger.yml	Adds Danger workflow using danger-pr-comment reusable workflow
.github/workflows/danger-comment.yml	Adds workflow to post Danger comments after PR validation
Gemfile	Adds danger-pr-comment gem and removes version constraints from danger-changelog and danger-toc
Dangerfile	Updates to import danger-pr-comment and uses stricter check! methods
README.md	Updates CI badge from Travis CI to GitHub Actions test workflow
CHANGELOG.md	Documents the migration in the changelog
.travis.yml	Removes Travis CI configuration file

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[Copilot]

The 'danger' gem is added without a version constraint. Consider adding a version constraint for better dependency management and reproducibility, similar to how other gems in the Gemfile specify versions (e.g., 'rspec', 'rubocop').

Suggested change

	gem 'danger'
	gem 'danger', '~> 9.0'

[Copilot]

Version constraints were removed from 'danger-changelog' (previously '> 0.4.0') and 'danger-toc' (previously '> 0.1'). This could lead to unexpected behavior if newer versions introduce breaking changes. Consider retaining version constraints for stability and reproducibility.

Suggested change

	gem 'danger-changelog'
	gem 'danger-pr-comment', '0.1.0'
	gem 'danger-toc'
	gem 'danger-changelog', '~> 0.4.0'
	gem 'danger-pr-comment', '0.1.0'
	gem 'danger-toc', '~> 0.1'