Add note about indexes to README #42

	name: CI RSpec Test

	on: [push, pull_request]

	jobs:
	build:
	name: >-
	${{ matrix.ruby }}
	env:
	CI: true
	TESTOPTS: -v
	runs-on: ubuntu-latest
	continue-on-error: ${{ matrix.experimental }}
	strategy:
	fail-fast: false
	matrix:
	ruby: [2.7, 3.0, 3.1, 3.2, truffleruby]
	mongoid: [7, 8]
	experimental: [false]
	include:
	- ruby: 3.2
	mongoid: HEAD
	experimental: true
	- ruby: head
	mongoid: 7
	experimental: true
	- ruby: head
	mongoid: HEAD
	experimental: true
	- ruby: jruby
	mongoid: 8
	experimental: true
	- ruby: jruby-head
	mongoid: 8
	experimental: true
	- ruby: truffleruby-head
	mongoid: 7
	experimental: true

	steps:
	- name: repo checkout
	uses: actions/checkout@v2

	- name: start mongodb
	uses: supercharge/[email protected]
	with:
	mongodb-version: 4.4
	mongodb-replica-set: rs0

	- name: load ruby
	uses: ruby/setup-ruby@v1
	with:
	ruby-version: ${{ matrix.ruby }}
	bundler: 2

	- name: bundle install
	run: bundle install --jobs 4 --retry 3
	env:
	MONGOID_VERSION: ${{ matrix.mongoid }}

	- name: rubocop
	timeout-minutes: 5
	run: bundle exec rubocop
	continue-on-error: ${{ matrix.experimental }}
	env:
	MONGOID_VERSION: ${{ matrix.mongoid }}

	- name: test
	timeout-minutes: 10
	run: bundle exec rake spec
	continue-on-error: ${{ matrix.experimental }}
	env:
	MONGOID_VERSION: ${{ matrix.mongoid }}

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