Update Gitaly setup to handle the case of merge-train forgetting about tmp/run/.gitkeep causing FOSS stable branches to break
Investigating gitlab-org/release/tasks#3898 (closed) we discovered that
during the merge-train for FOSS we are losing tmp/run/.gitkeep
and this is breaking the CI on the stable branches.
As a solution let's update the Gitaly setup to make this folder if it doesn't already exist
Edited by Amy Phillips