Allow OpenSSL verifier to be called with NULL SNI #1296

	---
	name: "CITestsClang"

	on:
	push:
	branches:
	- master
	pull_request:
	branches:
	- master

	jobs:
	citests:
	name: CI-Tests-Clang
	runs-on: ubuntu-latest
	env:
	CC: clang
	CXX: clang++

	steps:
	- name: Checkout repository
	uses: actions/checkout@v2
	with:
	# We must fetch at least the immediate parents so that if this is
	# a pull request then we can checkout the head.
	fetch-depth: 2
	submodules: 'recursive'

	- name: Building picoquic
	run: \|
	sudo apt-get install clangd
	sudo apt-get install -y libssl-dev
	echo $CC
	echo $CXX
	$CC --version
	./ci/build_picotls.sh
	cmake -S . -B build
	cmake --build build

	- name: Perform Unit Tests
	run: \|
	ulimit -c unlimited -S
	cd build
	make test && QUICRESULT=$?
	if [[ ${QUICRESULT} == 0 ]]; then exit 0; fi;
	exit 1

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