Push release images to artifactapi docker-internal (#134)

Gitea's registry rejects blob HEADs with 401, so the v3.13.0 tag pipeline cannot push. Release images move to the in-cluster artifactapi docker-internal registry, which trusts the runner without credentials.

- push docker-api to docker-internal/artifactapi and docker-web to docker-internal/artifactapi-ui
- use the CA-baked docker-internal/plugin-docker-buildx image
- drop the droneci credentials
- set kubernetes resources and service account on both steps

Reviewed-on: #134
Co-authored-by: unkin-agent <unkin-agent@unkin.net>
Co-committed-by: unkin-agent <unkin-agent@unkin.net>

.woodpecker/docker.yaml

@@ -4,31 +4,45 @@ when:
 
 steps:
   - name: docker-api
-    image: woodpeckerci/plugin-docker-buildx
+    image: artifactapi.k8s.syd1.au.unkin.net/docker-internal/plugin-docker-buildx:latest
     settings:
-      registry: git.unkin.net
-      repo: git.unkin.net/unkin/artifactapi
+      registry: artifactapi.k8s.syd1.au.unkin.net
+      repo: artifactapi.k8s.syd1.au.unkin.net/docker-internal/artifactapi
       build_args:
         VERSION: ${CI_COMMIT_TAG}
-      username: droneci
-      password:
-        from_secret: DRONECI_PASSWORD
       tags:
         - ${CI_COMMIT_TAG}
         - latest
+    backend_options:
+      kubernetes:
+        serviceAccountName: default
+        resources:
+          requests:
+            memory: 1Gi
+            cpu: 1
+          limits:
+            memory: 4Gi
+            cpu: 2
 
   - name: docker-web
-    image: woodpeckerci/plugin-docker-buildx
+    image: artifactapi.k8s.syd1.au.unkin.net/docker-internal/plugin-docker-buildx:latest
     settings:
-      registry: git.unkin.net
-      repo: git.unkin.net/unkin/artifactapi-ui
+      registry: artifactapi.k8s.syd1.au.unkin.net
+      repo: artifactapi.k8s.syd1.au.unkin.net/docker-internal/artifactapi-ui
       dockerfile: ui/Dockerfile.ui
       context: ui
       build_args:
         BASE_PATH: /ui
-      username: droneci
-      password:
-        from_secret: DRONECI_PASSWORD
       tags:
         - ${CI_COMMIT_TAG}
         - latest
+    backend_options:
+      kubernetes:
+        serviceAccountName: default
+        resources:
+          requests:
+            memory: 1Gi
+            cpu: 1
+          limits:
+            memory: 4Gi
+            cpu: 2