PHP_TAG=7.4-dev-4.23.0 issue with DNS

[davo20019]

I just tried to set up a local site using docker4drupal and I got errors when trying to install Drupal contrib modules using composer.

Steps to replicate:

1. Run the composer command: composer require 'drupal/externalauth:^1.3'
2. The error that I got was:

[Composer\Downloader\TransportException]                                                        
  The "https://packages.drupal.org/8/drupal/provider-2021-1%24a866ea7e150797c1a5afb99f41e4ec5e60  
  7e3f85c533951d71db14199b5b149c.json" file could not be downloaded: php_network_getaddresses: g  
  etaddrinfo failed: Name does not resolve                                                        
  failed to open stream: php_network_getaddresses: getaddrinfo failed: Name does not resolve

When I ran the composer diagnose command I got this as part of the output:

Checking github.com rate limit: FAIL
[Composer\Downloader\TransportException] The "https://api.github.com/rate_limit" file could not be downloaded: php_network_getaddresses: getaddrinfo failed: Name does not resolve
failed to open stream: php_network_getaddresses: getaddrinfo failed: Name does not resolve

In the .env file, I switched the PHP version to PHP_TAG=7.4-dev-4.21.4 and I am able to run composer commands again.

I am not sure if this is the right place to report this.

Thanks!