Grant permission to post on PubSub cloud functions

[dev-mansonthomas]

example :
gcloud alpha functions add-iam-policy-binding notifyRQOfRegistApproval --region=europe-west1 --member=allUsers --role=roles/cloudfunctions.invoker

[dev-mansonthomas]

gcloud alpha functions add-iam-policy-binding ULTriggerRecompute --region=europe-west1 --member=allUsers --role=roles/cloudfunctions.invoker
gcloud alpha functions add-iam-policy-binding ULQueteurStatsPerYear --region=europe-west1 --member=allUsers --role=roles/cloudfunctions.invoker