Remove "require 'thread'" statements #1504

	name: CI
	on: [push, pull_request]
	permissions:
	contents: read

	jobs:
	specs:
	strategy:
	fail-fast: false
	matrix:
	os: [ ubuntu, macos, windows ]
	ruby: [ 3.0.6, 3.1.4, 3.2.2 ]
	runs-on: ${{ matrix.os }}-latest
	steps:
	- name: git config autocrlf
	run: git config --global core.autocrlf false
	if: matrix.os == 'windows'

	- uses: actions/checkout@v4
	- uses: ruby/setup-ruby@v1
	with:
	ruby-version: ${{ matrix.ruby }}
	bundler: none
	- name: Clone MSpec
	run: git clone https://github.com/ruby/mspec.git ../mspec

	- name: Run specs (Linux)
	if: matrix.os == 'ubuntu'
	env:
	CHECK_LEAKS: true
	run: ../mspec/bin/mspec -j --timeout 30

	- name: Run specs (macOS)
	if: matrix.os == 'macos'
	env:
	CHECK_LEAKS: true
	# Use a larger timeout on macOS since it seems to have less reliable performance
	run: ../mspec/bin/mspec -j --timeout 90

	- name: Run specs (Windows)
	if: matrix.os == 'windows'
	env:
	CHECK_LEAKS: true
	run: \|
	# Actions uses UTF8, causes test failures, similar to normal OS setup
	[Console]::OutputEncoding = [System.Text.Encoding]::GetEncoding("IBM437")
	[Console]::InputEncoding = [System.Text.Encoding]::GetEncoding("IBM437")
	../mspec/bin/mspec -j

	- name: Run C-API specs as C++
	if: matrix.os != 'windows'
	env:
	SPEC_CAPI_CXX: true
	run: ../mspec/bin/mspec :capi

	- name: Run require_relative checker
	if: matrix.os == 'ubuntu'
	run: ../mspec/tool/check_require_spec_helper.rb

	rubocop:
	name: RuboCop
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: ruby/setup-ruby@v1
	with:
	ruby-version: '3.0'
	- run: gem install rubocop:1.28.2
	- run: rubocop --parallel

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