Merge pull request woocommerce/woocommerce-admin#2640 from woocommerce/fix/ci-tests-woo-deps

Tests setup: bring in Woo Core dependencies

plugins/woocommerce-admin/bin/install-wp-tests.sh

@@ -180,6 +180,11 @@ install_deps() {
 	cd "wp-content/plugins/"
 	# As zip file does not include tests, we have to get it from git repo.
 	git clone --depth 1 https://github.com/woocommerce/woocommerce.git
+
+	# Bring in WooCommerce Core dependencies
+	cd "woocommerce"
+	composer install --no-dev
+
 	cd "$WP_CORE_DIR"
 	php wp-cli.phar plugin activate woocommerce