set user to tex for tests run on ci box

services/clsi/docker-compose-config.yml

@@ -18,7 +18,7 @@ services:
   ci:
     environment:
       TEXLIVE_IMAGE: quay.io/sharelatex/texlive-full:2017.1
-      TEXLIVE_IMAGE_USER: root
+      TEXLIVE_IMAGE_USER: tex
       SHARELATEX_CONFIG: /app/config/settings.defaults.coffee
       DOCKER_RUNNER: "true"
       COMPILES_HOST_DIR: $PWD/compiles