Fix paths in grist.sh (#8777)

Author: mrinaldi

ct/grist.sh

@@ -36,13 +36,13 @@ function update_script() {
 
     msg_info "Creating backup"
     rm -rf /opt/grist_bak
-    mv grist grist_bak
+    mv /opt/grist /opt/grist_bak
     msg_ok "Backup created"
 
     fetch_and_deploy_gh_release "grist" "gristlabs/grist-core" "tarball"
 
     msg_info "Updating ${APP}"
-    mkdir -p grist/docs
+    mkdir -p /opt/grist/docs
     cp -n /opt/grist_bak/.env /opt/grist/.env
     cp -r /opt/grist_bak/docs/* /opt/grist/docs/
     cp /opt/grist_bak/grist-sessions.db /opt/grist/grist-sessions.db