Revert "Modify file_size help doc string (hardbyte#1401)"

This reverts commit b639560.

Author: j-c-cook

can/logger.py

@@ -193,10 +193,9 @@ def main() -> None:
         "--file_size",
         dest="file_size",
         type=int,
-        help="Maximum file size in bytes. Rotate log file when size threshold "
-        "is reached. (The resulting file sizes will be consistent, but are not "
-        "guaranteed to be exactly what is specified here due to the rollover "
-        "conditions being logger implementation specific.)",
+        help="Maximum file size in bytes (or for the case of blf, maximum "
+        "buffer size before compression and flush to file). Rotate log "
+        "file when size threshold is reached.",
         default=None,
     )