Fix logic error with AMI GC (#97)

Remove a stray `break` that was causing AMIs to not be GC'd.

Author: KyleFromNVIDIA

gc/collectors/amis.py

@@ -72,7 +72,6 @@ def _find_expired_amis(self, amis: list[ImageTypeDef]) -> list[ImageTypeDef]:
                 if image_name:
                     if branch_name:
                         ami_groups[branch_name][image_name].append(ami)
-                        break
                     else:
                         expired_amis.append(ami)