Fixing docs

Signed-off-by: Giuseppe Bertone <[email protected]>

README.md

@@ -43,12 +43,14 @@ If you have any questions on the Hedera SDK or Hedera more generally, you can jo
 Before running the integration tests, an operator key, operator account id, and a network name must be set in an `.env` file.
 
 ```bash
-# Account that will pay query and transaction fees
+# Account that will pay query and transaction fees.
 TEST_OPERATOR_ACCOUNT_ID=
-# Default private key to use to sign for all transactions and queries
+# Default private key to use to sign for all transactions and queries.
 TEST_OPERATOR_KEY=
-# Network names: "localhost", "testnet", "previewnet", "mainnet"
+# Network names: "localhost", "testnet", "previewnet", "mainnet".
 TEST_NETWORK_NAME=
+# Running on-chain tests if this value is set to 1.
+TEST_RUN_NONFREE=
 ```
 
 Run the tests using `cargo test`