ci: Install Docker 스텝 제거 + version bump

gitea/runner-images:ubuntu-latest 러너 이미지에 Docker가 이미 포함되어
있어 재설치 시도 시 dpkg 충돌 발생. 스텝 제거로 해결.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.github/workflows/build.yaml

@@ -30,12 +30,6 @@ jobs:
         echo "content=$VERSION" >> $GITHUB_OUTPUT
         echo "Version: $VERSION"
 
-    - name: Install Docker // Docker 설치
-      run: |
-        curl -fsSL https://get.docker.com -o get-docker.sh
-        sh get-docker.sh
-      if: runner.os == 'Linux'
-
     - name: Set up Docker Buildx
       # uses: https://github.com/docker/setup-buildx-action@v1
       uses: docker/setup-buildx-action@v1