Change build environment from debian to ubuntu-latest in GitHub Actions workflow

.gitea/workflows/build.yaml

@@ -14,7 +14,7 @@ on:
 
 jobs:
   build:
-    runs-on: debian
+    runs-on: ubuntu-latest
     env:
       SERVER_URL: ${{ gitea.server_url }}
       OWNER: ${{ gitea.repository_owner }}
@@ -36,16 +36,16 @@ jobs:
         env:
           NODE_EXTRA_CA_CERTS: /etc/ssl/certs/ca-certificates.crt
 
-      # node:24-trixie (Debian 13) has git and node but no Docker CLI. Install
-      # the CLI and buildx from Docker's apt repo; the daemon is the runner's.
+      # The Ubuntu runner image may not include the Docker CLI. Install the
+      # CLI and buildx from Docker's apt repo; the daemon is the runner's.
       - name: Install Docker CLI
         run: |
           install -m 0755 -d /etc/apt/keyrings
-          curl -fsSL https://download.docker.com/linux/debian/gpg -o /etc/apt/keyrings/docker.asc
+          curl -fsSL https://download.docker.com/linux/ubuntu/gpg -o /etc/apt/keyrings/docker.asc
           chmod a+r /etc/apt/keyrings/docker.asc
           cat > /etc/apt/sources.list.d/docker.sources <<SRC
           Types: deb
-          URIs: https://download.docker.com/linux/debian
+          URIs: https://download.docker.com/linux/ubuntu
           Suites: $(. /etc/os-release && echo "$VERSION_CODENAME")
           Components: stable
           Signed-By: /etc/apt/keyrings/docker.asc