[ShadowServer] Verification

[pdamoune]

Description

• README:
  • ❌ Remove text about logger
  • ❌ Add configuration guidelines
• ❌ Remove usage of update_existing_data
• ❌ Implement traceback like the template / best practices
• ❌ Remove pycti entity aliases in imports ( as ...)
• ❌ Requirement
  • ❌ Add fixed versions
  • ❌ Add stix2 library
• ❌ Add config.yaml configuration