Error when builing Docker image

[svetasmirnova]

Describe the bug

When I try to build a Docker image, I get error:

=> [build-env 6/7] RUN go mod download                                                                                                                                                              31.7s 
=> ERROR [build-env 7/7] RUN go build ./cmd/subfinder                                                                                                                                               10.4s 
------                                                                                                                                                                                                     
> [build-env 7/7] RUN go build ./cmd/subfinder:                                                                                                                                                           
8.498 # github.com/projectdiscovery/fastdialer/fastdialer/metafiles                                                                                                                                        
8.498 /go/pkg/mod/github.com/projectdiscovery/[email protected]/fastdialer/metafiles/shared.go:49:21: undefined: sync.OnceFunc                                                                            
8.498 /go/pkg/mod/github.com/projectdiscovery/[email protected]/fastdialer/metafiles/shared.go:73:19: undefined: sync.OnceFunc
8.498 note: module requires Go 1.21
------
Dockerfile:8
--------------------
  6 |     WORKDIR /app/v2
  7 |     RUN go mod download
  8 | >>> RUN go build ./cmd/subfinder
  9 |     
 10 |     # Release
--------------------
ERROR: failed to solve: process "/bin/sh -c go build ./cmd/subfinder" did not complete successfully: exit code: 1

After changing Dockerfile as

$ git diff
diff --git a/Dockerfile b/Dockerfile
index 3d5f71f..99c6783 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,5 +1,5 @@
 # Build
-FROM golang:1.20.6-alpine AS build-env
+FROM golang:1.21-alpine AS build-env

The docker image compiles fine.

Subfinder version

$ docker run subfinder -version
[INF] Current Version: v2.6.5
[INF] Subfinder Config Directory: /root/.config/subfinder

Complete command you used to reproduce this
docker build -t subfinder .