bundle exec jekyll build - Error

[devilmind81]

Hello,
I'm obtaining this error during docker container startup:

bundle exec jekyll build
Configuration file: /srv/jekyll/_config.yml
       Deprecation: The 'gems' configuration option has been renamed to 'plu
gins'. Please update your config file accordingly.
            Source: /srv/jekyll
       Destination: /srv/jekyll/_site
 Incremental build: disabled. Enable with --incremental
      Generating...
   GitHub Metadata: No GitHub API authentication could be found. Some fields
 may be missing or have incorrect data.
                    done in 3.503 seconds.
 Auto-regeneration: disabled. Use --watch to enable.
Running ["ScriptCheck", "LinkCheck", "ImageCheck", "HtmlCheck"] on ["./
_site"] on *.html...


Checking 32 external links...
Ran on 6 files!


- ./_site/bugs/index.html
  *  External link https://github.com/grafeas/issues/issues/new failed: 404 No error
rake aborted!
HTML-Proofer found 1 failure!
/usr/local/bundle/gems/html-proofer-3.7.3/lib/html-proofer/runner.rb:167:in `print_failed_tests'
/usr/local/bundle/gems/html-proofer-3.7.3/lib/html-proofer/runner.rb:48:in `run'
/srv/jekyll/Rakefile:7:in `block in <top (required)>'
Tasks: TOP => test
(See full trace by running task with --trace)

Can you help me pls?