feat: improve docker image

Dockerfile

@@ -1,12 +1,28 @@
-FROM golang:1.17 AS builder
-WORKDIR /source
-COPY go.mod .
-COPY go.sum .
+ARG GO_VERSION=1.17
+
+## Build container
+FROM golang:${GO_VERSION}-alpine AS builder
+
+RUN mkdir /user && \
+    echo 'nobody:x:65534:65534:nobody:/:' > /user/passwd && \
+    echo 'nobody:x:65534:' > /user/group
+
+RUN apk add --no-cache ca-certificates git zip
+
+WORKDIR /src
+
+COPY ./go.mod ./go.sum ./
 RUN go mod download
-COPY . .
-RUN CGO_ENABLED=0 GOOS=linux go build -a -o teledock ./cmd/teledock/main.go
 
-FROM scratch
-WORKDIR /bot/
-COPY --from=builder /source/teledock .
-CMD ["./teledock"]
+COPY ./ ./
+RUN CGO_ENABLED=0 go build -installsuffix 'static' -o /teledock /src/cmd/teledock
+
+## Final container
+FROM scratch AS final
+
+COPY --from=builder /user/group /user/passwd /etc/
+COPY --from=builder /teledock /teledock
+
+USER 65534:65534
+
+ENTRYPOINT ["/teledock"]