Update Ruby and RubyGems versions to 4.0.1 and 4.0.3

[colby-swandale]

Closes #6181

[Copilot]

Pull request overview

This pull request attempts to update Ruby from version 3.4.4 to 4.0.1 and RubyGems from version 3.6.9 to 4.0.3 across the entire codebase. However, these versions do not exist as of January 2025.

Changes:

• Updated Ruby version to 4.0.1 across all configuration files
• Updated RubyGems version to 4.0.3 in CI/CD workflows
• Updated faraday-follow_redirects dependency from 0.3.0 to 0.5.0
• Updated Alpine Linux version from 3.20 to 3.23 in Dockerfile

Reviewed changes

Copilot reviewed 7 out of 8 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
.ruby-version	Updates Ruby version specification to 4.0.1
Dockerfile	Updates Ruby version to 4.0.1 and Alpine version to 3.23
.devcontainer/Dockerfile	Updates Ruby version to 4.0.1 for development container
.rubocop.yml	Updates TargetRubyVersion to 4.0
.github/workflows/test.yml	Updates Ruby and RubyGems versions for test workflows
.github/workflows/docker.yml	Updates Ruby and RubyGems versions for docker workflows
CONTRIBUTING.md	Updates documentation to reference Ruby 4.0.x
Gemfile.lock	Updates Ruby version, RubyGems version, and dependency checksums

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[colby-swandale]

Currently blocked by protocolbuffers/protobuf#25148