Removing a line from Procfile does not remove it from `gdk start`

detected in !844 (comment 238204669)

When you remove a line from the Procfile (for example when you disable praefect in that MR) it still starts all services which ever were set up for Runit:

echo "praefect:\n  enabled: false" >> gdk.yml
rake Procfile
gdk start

Which gave me:

(in /home/toon/devel/sandbox/gitlab-development-kit)
ok: run: ./services/gitaly: (pid 26916) 0s, normally down
ok: run: ./services/gitlab-pages: (pid 26923) 0s, normally down
ok: run: ./services/gitlab-workhorse: (pid 26918) 0s, normally down
ok: run: ./services/jaeger: (pid 26921) 0s, normally down
ok: run: ./services/minio: (pid 26922) 0s, normally down
ok: run: ./services/postgresql: (pid 26917) 0s, normally down
ok: run: ./services/praefect: (pid 26919) 0s, normally down
ok: run: ./services/praefect-gitaly-0: (pid 26920) 0s, normally down
ok: run: ./services/rails-background-jobs: (pid 26924) 0s, normally down
ok: run: ./services/rails-web: (pid 26925) 0s, normally down
ok: run: ./services/redis: (pid 26926) 0s, normally down
ok: run: ./services/registry: (pid 26927) 0s, normally down
ok: run: ./services/tunnel_gitlab: (pid 26932) 0s, normally down
ok: run: ./services/tunnel_registry: (pid 26945) 0s, normally down
ok: run: ./services/webpack: (pid 26954) 0s, normally down

praefect and praefect-gitaly-0 should not have been started.