Update rubocop and CI action versions

[fussy113]

Summary

This PR updates RuboCop and related dependencies to their latest versions,
and pins GitHub Actions to specific commit SHAs for improved security.

Motivation

CI failed: https://github.com/fussy113/rspec-snapshot/actions/runs/18465914526/job/52607732683

Rubocop and Actions version used CI was old, causing an error.

Changes

• Update actions version used CI
• Update Rubocop and Rubocop plugins version
• Fix .rubocop.yml
• Add rubocop_todo
  • It should fix. But the purpose is to pass CI, not the essence.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[Copilot]

Pull Request Overview

Updates RuboCop and GitHub Actions to resolve CI failures by upgrading to newer versions and improving security by pinning actions to specific commit SHAs.

• Updated RuboCop and its plugins (rubocop-rake, rubocop-rspec) to latest versions
• Pinned GitHub Actions to specific commit SHAs for enhanced security
• Added rubocop_todo.yml to temporarily disable failing RSpec rules

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
Gemfile	Updates RuboCop and plugin versions to latest releases
.rubocop_todo.yml	Adds temporary exclusions for RSpec/ExpectInLet violations
.rubocop.yml	Updates configuration syntax and replaces deprecated rules
.github/workflows/ci.yml	Pins actions to specific commit SHAs for security

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