specify "prod" as the docker build target

locally, docker build works as expected. When not specifying a build target, it builds the last target specified in the Dockerfile (in this case "prod"). On GitHub actions this works properly as well.
However, there seems to be something about the version of docker used on Drone that causes it to build all of the stages (and hence failing on enterprise-dev).

Let's instead just be explicit about which build target to use for both drone and GitHub actions.

.drone.yml

@@ -104,6 +104,7 @@ steps:
       repo: us.gcr.io/kubernetes-dev/oncall
       dockerfile: engine/Dockerfile
       context: engine/
+      target: prod
       config:
         from_secret: gcr_admin
     depends_on:
@@ -117,6 +118,7 @@ steps:
       repo: grafana/oncall
       dockerfile: engine/Dockerfile
       context: engine/
+      target: prod
       password:
         from_secret: docker_password
       username:
@@ -146,9 +148,9 @@ services:
 trigger:
   event:
     include:
-    - tag
-    - push
-    - pull_request
+      - tag
+      - push
+      - pull_request
   ref:
     include:
       - refs/heads/main
@@ -196,7 +198,7 @@ steps:
       GRAFANA_API_KEY:
         from_secret: gcom_plugin_publisher_api_key
     commands:
-      - "curl -f -s -H \"Authorization: Bearer $${GRAFANA_API_KEY}\" -d \"download[any][url]=https://storage.googleapis.com/grafana-oncall-app/releases/grafana-oncall-app-${DRONE_TAG}.zip\" -d \"download[any][md5]=$$(curl -sL https://storage.googleapis.com/grafana-oncall-app/releases/grafana-oncall-app-${DRONE_TAG}.zip | md5sum | cut -d' ' -f1)\" -d url=https://github.com/grafana/oncall/grafana-plugin https://grafana.com/api/plugins"
+      - 'curl -f -s -H "Authorization: Bearer $${GRAFANA_API_KEY}" -d "download[any][url]=https://storage.googleapis.com/grafana-oncall-app/releases/grafana-oncall-app-${DRONE_TAG}.zip" -d "download[any][md5]=$$(curl -sL https://storage.googleapis.com/grafana-oncall-app/releases/grafana-oncall-app-${DRONE_TAG}.zip | md5sum | cut -d'' '' -f1)" -d url=https://github.com/grafana/oncall/grafana-plugin https://grafana.com/api/plugins'
     depends_on:
       - sign and package plugin
 
@@ -229,6 +231,7 @@ steps:
       repo: grafana/oncall
       tags: ${DRONE_TAG}-amd64-linux
       dockerfile: engine/Dockerfile
+      target: prod
       context: engine/
       password:
         from_secret: docker_password
@@ -266,6 +269,7 @@ steps:
       repo: grafana/oncall
       tags: ${DRONE_TAG}-arm64-linux
       dockerfile: engine/Dockerfile
+      target: prod
       context: engine/
       password:
         from_secret: docker_password
@@ -396,5 +400,3 @@ name: drone_token
 ---
 kind: signature
 hmac: 8a060649c132677ba1b5693b5ac6c846c02f9a5bb645fe990b26a7ea42a0fb66
-
-...

.github/workflows/ci.yml

@@ -152,5 +152,6 @@ jobs:
           context: ./engine
           file: ./engine/Dockerfile
           push: false
+          target: prod
       - name: Image digest
         run: echo ${{ steps.docker_build.outputs.digest }}