improve: production versions for GHA and docker-compose files

* GHA: only build when a tag beginning with "v" is pushed, drop development builds on every push to master/main/this PR branch
* docker-compose: use what I think could be the official GetODK image names, but final naming is up to the core team
* docker image versions: currently referring to "latest" for ease of testing, should be pinned before used in prod

.github/workflows/docker.yml

@@ -1,15 +1,12 @@
 # Workflow derived from https://github.com/r-lib/actions/tree/master/examples
 # Need help debugging build failures? Start at https://github.com/r-lib/actions#where-to-find-help
 # Publish `v1.2.3` tags as releases.
+
+# This GitHub Action runs whenever a git tag beginning with "v" is pushed. E.g., "v0.4.0".
 on:
   push:
     tags:
       - v*
-    # DEBUG: once working in upstream, drop the branches.
-    branches:
-      - main
-      - master
-      - '272-docker'
 
 name: docker
 
@@ -32,7 +29,7 @@ jobs:
         run: docker build . --file Dockerfile --tag $IMAGE_NAME --label "runnumber=${GITHUB_RUN_ID}"
 
       - name: Log in to registry
-        # This is where you will update the PAT to GITHUB_TOKEN
+        # Instead of a PAT, a GITHUB_TOKEN can be used
         run: echo "${{ secrets.GH_PAT }}" | docker login ghcr.io -u ${{ secrets.GH_ACTOR }} --password-stdin
 
       - name: Push image

docker-compose.dev.yml

@@ -14,8 +14,7 @@ services:
       POSTGRES_DATABASE: odkbuild
     restart: always
   build2xlsform:
-    # image: "ghcr.io/getodk/build2xlsform:latest"
-    image: "ghcr.io/florianm/odkbuild2xlsform:21-docker"
+    image: "ghcr.io/getodk/build2xlsform:latest"
     ports:
       - "8686:8686"
   odkbuild:

docker-compose.yml

@@ -14,8 +14,7 @@ services:
       POSTGRES_DATABASE: odkbuild
     restart: always
   build2xlsform:
-    # image: "ghcr.io/getodk/build2xlsform:latest"
-    image: "ghcr.io/florianm/odkbuild2xlsform:21-docker"
+    image: "ghcr.io/getodk/build2xlsform:latest"
     ports:
       - "8686:8686"
   odkbuild: