live: remove file from cache with no checksum file

Maybe result of a partial download? then, remove it to leave cache in consistent
state.

src/live/ogOperations.py

@@ -139,7 +139,16 @@ class OgLiveOperations:
                 logging.error(f'Cannot read checksum file {checksum_file_path}: {e}')
 
             if not image_checksum:
-                logging.error(f'Empty checksum for image {file_name}')
+                logging.info(f'Removing {file_name} with no checksum file from cache, maybe partial download?')
+                try:
+                if os.path.exists(file_path):
+                    os.unlink(file_path)
+                if os.path.exists(checksum_file_path):
+                    os.unlink(checksum_file_path)
+                except OSError as e:
+                    pass
+
+                continue
 
             image_size = os.stat(file_path).st_size
             cache_contents.append({