Passes env var during apt-test upgrade testing

Pointed out by @msheiny during review, so lifting the patch from PR
discussion and implementing to resolve. The goal is to ensure that the
"use apt-test repo" env var is declared during the "create" phase of the
scenario, which is now handled.

Makefile

@@ -167,6 +167,10 @@ clean: ## DANGER! Purges all site-specific info and developer files from project
 upgrade-start: ## Boot up an upgrade test base environment using libvirt
 	@SD_UPGRADE_BASE=$(STABLE_VER) molecule converge -s upgrade
 
+.PHONY: upgrade-start-qa
+upgrade-start-qa: ## Boot up an upgrade test base env using libvirt in remote apt mode
+	@SD_UPGRADE_BASE=$(STABLE_VER) QA_APTTEST=yes molecule converge -s upgrade
+
 .PHONY: upgrade-destroy
 upgrade-destroy: ## Destroy up an upgrade test base environment
 	@SD_UPGRADE_BASE=$(STABLE_VER) molecule destroy -s upgrade

docs/development/upgrade_testing.rst

@@ -79,7 +79,7 @@ create the environment:
 
 .. code:: sh
 
-   make upgrade-start
+   make upgrade-start-qa
 
 Then, log into the *Application Server*: