SKALE-2844 fix documenrtation

SEKManager.cpp

@@ -134,8 +134,8 @@ void gen_SEK(){
   std::ofstream sek_file("backup_key.txt");
   sek_file.clear();
 
-  cout << "ATTENTION! YOUR BACKUP KEY WILL BE WROTE INTO backup_key.txt.\n" <<
-          "PLEASE COPY IT TO THE SAFE PLACE AND THEN DELETE THE FILE MANUALLY RUNNING FOLLOWING COMMAND:\n" <<
+  cout << "ATTENTION! YOUR BACKUP KEY WILL BE WRITTEN INTO backup_key.txt.\n" <<
+          "PLEASE COPY IT TO THE SAFE PLACE AND THEN DELETE THE FILE MANUALLY BY RUNNING THE FOLLOWING COMMAND:\n" <<
           "`sudo apt-get install secure-delete && srm -vz backup_key.txt`" << endl;
   sek_file << SEK;
 

docs/backup-procedure.md

@@ -4,7 +4,8 @@
 
 When SGXWallet is initialized, the server will print the backup key. 
 **This key must be securely recorded and stored.**
-The key will be stored in file "backup_key.txt". Remove it once you store it in a safe place with following command:
+Be sure to store this key in a safe place, then securely remove it with the following command:
+
 ```bash
 sudo apt-get install secure-delete && srm -vz backup_key.txt
 ```