add comment explaining check_signature_shares test fn #401

	#on: [push, pull_request]
	on: [push]

	name: CI

	jobs:
	check:
	name: check
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- uses: actions-rs/toolchain@v1
	with:
	profile: minimal
	toolchain: stable
	override: true
	- uses: actions-rs/cargo@v1
	with:
	command: check

	test-all:
	name: test-all
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- uses: actions-rs/toolchain@v1
	with:
	profile: minimal
	toolchain: stable
	override: true
	- uses: actions-rs/cargo@v1
	with:
	command: test

	fmt:
	name: fmt
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- uses: actions-rs/toolchain@v1
	with:
	profile: minimal
	toolchain: stable
	override: true
	- run: rustup component add rustfmt
	- uses: actions-rs/cargo@v1
	with:
	command: fmt
	args: --all -- --check

	clippy:
	name: clippy
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- uses: actions-rs/toolchain@v1
	with:
	profile: minimal
	toolchain: stable
	override: true
	- run: rustup component add clippy
	- uses: actions-rs/cargo@v1
	with:
	command: clippy
	args: -- -D warnings -A clippy::op-ref -A clippy::needless-range-loop

	doc:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- uses: actions-rs/toolchain@v1
	with:
	profile: minimal
	toolchain: stable
	override: true
	- name: Install LaTeX
	run: ./.doc/install-latex-ubuntu.sh
	- name: Build WebSite
	run: ./.doc/build.sh
	- name: upload pdf
	uses: actions/upload-artifact@v3
	with:
	name: wsts.pdf
	path: wsts.pdf
	- name: upload website
	uses: actions/upload-artifact@v3
	with:
	name: website
	path: ./target/doc/

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