Fix: VM does not boot if no SSH key is specified

Problem: The authorized_keys file could not be generated if
the `config.authorized_keys` settings was None because it was
used in a list comprehension.

Solution: check for None early.

runtimes/aleph-debian-11-python/init1.py

@@ -173,7 +173,7 @@ def setup_input_data(input_data: bytes):
  os.system("unzip -q /opt/input.zip -d /data")
 
 
-def setup_authorized_keys(authorized_keys: Optional[List[str]]) -> None:
+def setup_authorized_keys(authorized_keys: List[str]) -> None:
  path = Path("/root/.ssh/authorized_keys")
  path.parent.mkdir(exist_ok=True)
  path.write_text("\n".join(key for key in authorized_keys))
@@ -510,7 +510,8 @@ def setup_system(config: ConfigurationPayload):
  dns_servers=config.dns_servers,
  )
  setup_input_data(config.input_data)
- setup_authorized_keys(config.authorized_keys)
+ if authorized_keys := config.authorized_keys:
+ setup_authorized_keys(authorized_keys)
  logger.debug("Setup finished")