Do not commit read-only transactions

This a marginal improvement which follows the C API documentation:
> It is not necessary to commit a read-only transaction – you can simply call fdb_transaction_destroy().

bindings/go/src/fdb/database.go

@@ -209,6 +209,7 @@ func (d Database) Transact(f func(Transaction) (interface{}, error)) (interface{
 //
 // The transaction is retried if the error is or wraps a retryable Error.
 // The error is unwrapped.
+// Read transactions are never committed and destroyed upon garbage collection.
 //
 // Do not return Future objects from the function provided to ReadTransact. The
 // Transaction created by ReadTransact may be finalized at any point after
@@ -230,9 +231,7 @@ func (d Database) ReadTransact(f func(ReadTransaction) (interface{}, error)) (in
 
 		ret, e = f(tr)
 
-		if e == nil {
-			e = tr.Commit().Get()
-		}
+		// read-only transactions are not committed and destroyed automatically on Go garbage collection
 
 		return
 	}