Use absolute path in example as it seems to be working now

Dependencies

• [2] Q2E4J3PH Update docs

Change contents

• replacement in doc/manual/src/configuration.md at line 28
  [2.741]→[2.741:776](∅→∅)
  − Include github_authorizations.conf
  [2.741]

  [2.776]
  + Include /run/keys/hydra/github_authorizations.conf