fix bug with cache cleaning time

grib_processor/utils.py

@@ -189,6 +189,7 @@ def realtime(file_iter: Iterable[str]) -> Generator[GribPayload, None, None]:
         if time.time() - last_clean_time > CACHE_CLEAN_INTERVAL:
             LOG.info("realtime - time to clean the cache")
             _clean_caches(cache)
+            last_clean_time = time.time()
 
 
 def grib_filter(change: Change, path: str) -> bool: