Move all custom branding block keys out of the theme `.info.yml` as that's not an appropriate place for them

[Ambient-Impact]

See https://github.com/Ambient-Impact/drupal-themes/blob/9edbd55cef0de9c15bf923749e95312ef1cc9764/ambientimpact_base/ambientimpact_base.theme#L128

Drupal\Core\Extension\InfoParserInterface::parse() states:

  /**
   * Parses Drupal module, theme and profile .info.yml files.
   *
   * Info files are NOT for placing arbitrary theme and module-specific
   * settings. Use Config::get() and Config::set()->save() for that. Info files
   * are formatted as YAML. If the 'version' key is set to 'VERSION' in any info
   * file, then the value will be substituted with the current version of Drupal
   * core.
   *
   * [...]
   */

Putting the values in config/install might be the best way to do it. Alternatively, defining a custom .yml file in the theme's directory for these values. See:

• Drupal\Component\Discovery\YamlDiscovery
• Drupal\Core\Discovery\YamlDiscovery