update readme, small fixes #8

	#=========================================================================
	# run-pymtl-tests.yml
	#=========================================================================
	# This workflow illustrates how to use the verilator-ci-cache with
	# GitHub actions to run pymtl3 tests.

	name: Test Verilator CI Cache

	on:
	push:
	branches: [ master ]
	pull_request:
	branches: [ master ]

	jobs:
	run_pymtl_tests:
	runs-on: ubuntu-22.04

	steps:
	- uses: actions/checkout@v4
	- uses: actions/setup-python@v5
	with:
	python-version: 3.11

	- name: Install verilator
	run: \|
	wget --progress=dot:giga https://github.com/pymtl/verilator-ci-cache/raw/master/verilator-github-actions-5.026.tar.gz
	echo $PWD
	whoami
	tar -C ${HOME} -xzf verilator-github-actions-5.026.tar.gz
	echo "${HOME}/verilator/bin" >> $GITHUB_PATH
	echo "PKG_CONFIG_PATH=${HOME}/verilator/share/pkgconfig:${PKG_CONFIG_PATH}" >> $GITHUB_ENV

	- name: Check verilator
	run: \|
	which verilator
	verilator --version
	pkg-config --modversion verilator
	pkg-config --cflags verilator

	- name: Install dependencies
	run: \|
	sudo apt-get install -y graphviz
	git clone https://github.com/pymtl/pymtl3
	cd pymtl3
	git checkout pymtl4.0-dev
	pip install --upgrade pip
	pip install -r requirements.txt
	pip install -e .
	pip list

	- name: Run tests
	run: \|
	mkdir -p pymtl3/build && cd pymtl3/build
	pytest ../pymtl3

Provide feedback