fix(docker): use 555 for binary (#499)

Author: tobiasehlert

Dockerfile

@@ -39,7 +39,7 @@ RUN apk --no-cache add ca-certificates tzdata && \
 USER nonroot:nonroot
 
 # copy binary from builder
-COPY --from=builder --chown=nonroot:nonroot --chmod=544 /go/src/app .
+COPY --from=builder --chown=nonroot:nonroot --chmod=555 /go/src/app .
 
 # expose port 8080
 EXPOSE 8080