try removing incremental build files to see if it helps ci disk usage

.drone.yml

@@ -1,11 +1,14 @@
 ---
 kind: pipeline
 type: docker
-name: test elseware 
+name: test elseware
 
 concurrency:
     limit: 1
 
+environment:
+  CARGO_INCREMENTAL: false
+
 steps:
 - name: clean cache
   image: rustlang/rust:nightly