chore: add max-storage-radius option to pt-testnet-load (#445)

Author: gacevicljubisa

config/public-testnet.yaml

@@ -135,6 +135,7 @@ checks:
       uploader-count: 2
       downloader-count: 0
       max-use-batch: 1h
+      max-storage-radius: 3
       upload-groups:
         - bee-1
         - bee-2