dev-python/invoke: explicitly load pytest-relaxed plugin

Bug: https://bugs.gentoo.org/661218
Package-Manager: Portage-2.3.44, Repoman-2.3.10

dev-python/invoke/invoke-1.1.0.ebuild

@@ -29,5 +29,6 @@ PATCHES=(
 
 python_test() {
 	# -s flag is important: tests fail when pytest isn't in "no capture" mode
-	${EPYTHON} -m pytest -s -v
+	# -p pytest_relaxed: this plugin has to be loaded explicitly
+	pytest -s -v -p pytest_relaxed.plugin || die "Tests failed"
 }