Set drone secrets to environment

.drone.yml

@@ -12,8 +12,9 @@ pipeline:
         environment:
             - CFLAGS=-O0
             - DB_CACHE=/cache
-            - TOX_TESTENV_PASSENV=CFLAGS DB_CACHE CI_BUILD_NUMBER CI_JOB_NUMBER CI_JOB_ID
+            - TOX_TESTENV_PASSENV=CFLAGS DB_CACHE CI_BUILD_NUMBER CI_JOB_NUMBER CI_JOB_ID SENDCLOUD_PUBLIC_KEY SENDCLOUD_SECRET_KEY
             - POSTGRESQL_URI=postgresql://postgres@postgresql:5432/
+        secrets: [ sendcloud_public_key, sendcloud_secret_key ]
         commands:
             - echo "[extensions]" >> /root/.hgrc
             - echo "hgext.share =" >> /root/.hgrc