fix: execute functional tests from Makefile (#362)

The `ARTIFACTS_PATH` variable was not passed to the
`run-functional-test` script.

Signed-off-by: Nestor Acuna Blanco <[email protected]>

Author: nestoracunablanco

Makefile

@@ -93,7 +93,7 @@ test:
 	hack/language.sh
 
 test-functional:
-	hack/run-functional-test.sh
+	ARTIFACTS_PATH=$(ARTIFACTS_PATH) hack/run-functional-test.sh
 
 test-sanity: generate-doc lint-metrics
 	hack/sanity.sh