update drone.yml

drone.yml

     DEBUG: true
   commands:
     - export PATH=$PATH
-    - echo 'Acquire::http { Proxy "http://unino.de:3142"; }' | sudo tee -a /etc/apt/apt.conf.d/proxy
+    - echo 'Acquire::http { Proxy "http://unino.de:3142"; }' | tee -a /etc/apt/apt.conf.d/proxy
     - apt-get update
     - apt-get --yes upgrade
     - apt-get --yes install build-essential libc6-dev libhidapi-dev libssl-dev