Bump virtualenv from 20.28.0 to 20.28.1 in /backend in the dev-deps group #239

Job	Run time
gitleaks	9s
build-docker / Build Backend	1m 6s
test-backend	1m 10s
prepare-frontend-environment	1m 7s
test-frontend	3m 38s
qa-frontend	52s
	8m 2s

Provide feedback