Update .drone.yml

Changed image to rust:alpine

We don't have to specifically build for rust 1.66.1 (what RL9 currently uses), since we can build it with a runner and deploy the runner, with all libraries statically linked.

.drone.yml

@@ -6,7 +6,7 @@ platform:
 
 steps:
 - name: test
-  image: rust:1.66.1-alpine
+  image: rust:alpine
   commands:
   - rustc --version
   - cargo --version
@@ -21,7 +21,7 @@ platform:
 
 steps:
 - name: test
-  image: rust:1.66.1-alpine
+  image: rust:alpine
   commands:
   - rustc --version
   - cargo --version