Update CI

.drone.yml

@@ -4,12 +4,14 @@ type: docker
 name: default
 
 steps:
-  - name: cmake
+  - name: build
     image: ghcr.io/rikorose/gcc-cmake
     commands:
       - mkdir build && cd build
       - cmake ..
+      - make
   - name: docs
     image: docker.io/corentinaltepe/doxygen
     commands:
-      - ls -l
+      - doxygen
+      - ls docs