Improve CI

Add more tests to the CI, including a docker build test, and add the
generation and publication of a new docker image on master and tags

.drone.yml

@@ -3,38 +3,23 @@ type: docker
 name: Tests
 
 steps:
-- name: go-test
+- name: Go tests
   image: golang
   commands:
   - make -C tracker test
-  depends_on:
 
-- name: go-build
+- name: Go build
   image: golang
   commands:
   - make -C tracker build
-  depends_on:
 
-- name: docker-build
+- name: Docker build
   image: thegeeklab/drone-docker-buildx
   privileged: true
   settings:
-    repo: git.faercol.me/faercol/public-ip-tracker
-    tags: latest
     platforms:
       - linux/amd64
       - linux/arm64
-  depends_on:
-
-- name: docker-push
-  image: thegeeklab/drone-docker-buildx
-  privileged: true
-  settings:
-    repo: git.faercol.me/faercol/public-ip-tracker
-  depends_on:
-    - go-test
-    - go-build
-    - docker-build
 
 trigger:
   event: