feat(docker): add a CI/CD Dockerfile, which starts the server right away (#10933)

Dockerfile.cicd

@@ -0,0 +1,36 @@
+FROM golang:1.15-alpine as builder
+
+LABEL maintainer="MinIO Inc <dev@min.io>"
+
+ENV GOPATH /go
+ENV CGO_ENABLED 0
+ENV GO111MODULE on
+
+RUN  \
+  apk add --no-cache git && \
+  git clone https://github.com/minio/minio && cd minio && \
+  git checkout master && go install -v -ldflags "$(go run buildscripts/gen-ldflags.go)"
+
+FROM alpine:3.12
+
+ENV MINIO_ACCESS_KEY_FILE=access_key \
+  MINIO_SECRET_KEY_FILE=secret_key \
+  MINIO_KMS_MASTER_KEY_FILE=kms_master_key \
+  MINIO_SSE_MASTER_KEY_FILE=sse_master_key \
+  MINIO_UPDATE_MINISIGN_PUBKEY="RWTx5Zr1tiHQLwG9keckT0c45M3AGeHD6IvimQHpyRywVWGbP1aVSGav"
+
+EXPOSE 9000
+
+COPY --from=builder /go/bin/minio /usr/bin/minio
+COPY --from=builder /go/minio/CREDITS /third_party/
+COPY --from=builder /go/minio/dockerscripts/docker-entrypoint.sh /usr/bin/
+
+RUN  \
+  apk add --no-cache ca-certificates 'curl>7.61.0' 'su-exec>=0.2' && \
+  echo 'hosts: files mdns4_minimal [NOTFOUND=return] dns mdns4' >> /etc/nsswitch.conf
+
+ENTRYPOINT ["/usr/bin/docker-entrypoint.sh"]
+
+VOLUME ["/data"]
+
+CMD ["minio", "server", "/data"]