BillboardEffect: Update parameter name case #316

	name: Continuous Integration
	on: [push, pull_request]
	jobs:
	lint:
	name: Lint
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v1
	- uses: actions/setup-python@v1
	with:
	python-version: '3.7'
	- name: Install requirements
	run: \|
	pip install -r requirements.txt
	pip install flake8 doc8
	- name: Test Python code style
	run: \|
	flake8
	- name: Test reStructuredText code style
	run: \|
	doc8 --ignore=D001
	#- name: Run linkcheck
	# run: \|
	# make linkcheck

	build-html:
	name: Build HTML
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v1
	- uses: actions/setup-python@v1
	with:
	python-version: '3.7'
	- name: Install requirements
	run: \|
	sudo apt-get install --no-install-recommends graphviz
	pip install -r requirements.txt
	pip uninstall -y panda3d
	- name: Build HTML manual
	run: \|
	make html

	build-pdf:
	name: Build PDF
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v1
	- uses: actions/setup-python@v1
	with:
	python-version: '3.7'
	- name: Install requirements
	run: \|
	sudo apt-get install --no-install-recommends graphviz latexmk texlive-fonts-recommended texlive-latex-extra tex-gyre
	pip install -r requirements.txt
	- name: Build PDF manual
	run: \|
	make latexpdf

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