我正在尝试在Nexus 3中为GitLab容器注册表中托管的Docker映像配置Docker代理存储库。我可以使用以下命令成功执行拉取：
docker pull gitlab.masked.url:5443/masked-group/masked-project/masked-image:latest
要在Nexus中配置代理存储库，请使用以下设置：
Name: dockertest
Format: docker
Type: proxy
Url: https://nexus.masked.url/repository/dockertest/
Online: true
Remote storage: https://gitlab.masked.url:5443
Use certificates stored in the Nexus truststore...: true
Docker index: Use proxy registry (specified above)
HTTP Authentication: true
Authentication type: Username
Username: foo
Password: ***
其他所有内容均保留为默认值。现在，如果我执行
docker pull nexus.masked.url:443/repository/dockertest/masked-group/masked-project/masked-image:latest
我收到以下答复：
Error response from daemon: error parsing HTTP 404 response body: invalid character '<' looking for beginning of value: "\n<!DOCTYPE html>\n<html lang=\"en\">\n<head>\n <title>404 - Nexus Repository Manager</title>\n...
我的配置出了什么问题？