Handle dependencies not existing before

[kam193]

If a dependency didn't exist before, there is no existing dependency blob key.

For example, introducing a new dependency to the existing service, results in
the following error on updating:

Error applying service settings from: Network-Information\nTraceback (most recent call last):
  File \"/var/lib/assemblyline/.local/lib/python3.11/site-packages/assemblyline_core/scaler/scaler_server.py\", line 626, in _sync_service
    if profile.dependency_blobs[dependency_name] != dependency_blob:
       ~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^\nKeyError: 'netinfo_cache'

A similar error appears if you try to rename a dependency