Remove blobs_db when purge-db (#5081)

beacon_node/src/config.rs

@@ -62,6 +62,13 @@ pub fn get_config<E: EthSpec>(
             fs::remove_dir_all(freezer_db)
                 .map_err(|err| format!("Failed to remove freezer_db: {}", err))?;
         }
+
+        // Remove the blobs db.
+        let blobs_db = client_config.get_blobs_db_path();
+        if blobs_db.exists() {
+            fs::remove_dir_all(blobs_db)
+                .map_err(|err| format!("Failed to remove blobs_db: {}", err))?;
+        }
     }
 
     // Create `datadir` and any non-existing parent directories.